HOT AIR TURBO/SFI

V-6 NOTES

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

84-85 Turbo 3.8 Liter Engine Sensors


ECM Harness

1. Electronic Control Module (ECM)
2. Assembly Line Diagnostic Link (ALDL) Connector
3. Service Engine Soon Light
4. ECM +12 Volt Connection
5. ECM Harness Ground
6. Fuse Panel


Not ECM Connected

7. Fuel Filter
8. Positive Crankcase Ventilation (PCV) Valve
9. N/A
10. Turbocharger


 

Controlled Devices

11. Fuel Injectors (6)
12. Idle Air Control (IAC) Motor
13. Fuel Pump Relay
14. Transmission Converter Clutch (TCC) Connector
15. Computer Controlled Coil (C3I) Ignition
16. Electronic Spark Control (ESC) Module
17. Exhaust Gas Recirculation (EGR) Vacuum Solenoid
18. Air Conditioning Compressor Relay
19. Fuel Vapor Canister Solenoid
20. Wastegate Control Solenoid


Information Sensors

25. Exhaust Oxygen (O2)
26. Throttle Position (TPS)
27. Coolant Temperature
28. Camshaft Position
29. Crankshaft Position
30. Mass Air Flow (MAF)
31. Knock Sensor
32. Transmission Park/Neutral (PN) Switch
33. Vehicle Speed Sensor (VSS)
34. MAP Sensor

 

The perfect place to add a remote oil pressure sensor is the back of block. Remove the passengers side galley plug (must be passengers side) install fitting and run a hard (pre-made) brake line up through a hole that you will have to drill beside the knock sensor. Then put the oil pressure sensor at the rear of engine.

 


Type 1 Module is available from GM PartsDirect.com, P/N 24503624 for $154.06.

Coil Pack is available at Summit P/N ACC-140016 for $85.95



 

 

 

 

1984-1985 Turbo Regal Common Parts

gnttype-webmaster@gnttype.org

GM and Non-GM Parts

 

Coil

25533542

Coil-to-ignition module gasket

25526450

Fuel pressure regulator, Turbo TA and Somerset

25523720

Head bolts - torque to yield Long

25525953

Short

25527831

Ignition Module

25526449

Turbo Inlet Gasket - Rivera

1261269

Seal adapter to turbo ( o-ring )

25515935

Seal adapter to intake ( o-ring )

1262817

Wastegate - adjustable

25527603

Non GM parts

 

Larger rear brake cylinders GM

18012305

EIS

104432

Bendix

33892

Felpro Gaskets Exhaust

1400

Felpro Gaskets Intake

1200

Felpro Gaskets Heads (4.1)

1026

Main seal kit

BS40613

Higher Capacity Oil Filters

 

AC

PF-52

Fram

3980

Bosch O2 Sensors

0-258-002-019

Fuel Injector O rings (Also for regulator)

SK1 RN7

Remote Oil pressure sending unit (like used on the GNX) Stewart-Warner

F-279B

Walker Super Turbo DynoMax Mufflers (2 1/4" in/out)

17731

K & N Filters Stock Replacement style

RE-0910

 

 

 

 

 

GM and Non-GM Parts

 

DESCRIPTION

PART NUMBER

NOTE

A/C compressor spacer .030" to align pulleys

14047730

.

AC/Delco Tread Sealer with Teflon

14011040

.

Bolt, Rod Cap

25531956

.

Bolt, Main Cap

25517607

.

Bolt, Head -torque to yield Long

25525953

.

Bolt, Head-torque to yield Short

25527831

.

Boost Solenoid

1997157

.

Brace, Alternator accessory

25525338

Discontinued

Calpack

16036503

Alternate: 16036504

Cam thrust button w/needle bearings

25532588

.

Cam Sprocket(nylon over teeth)

25523115

 

Coil-to-ignition module screw

25533541

.

Coil-to-ignition module gasket

25526450

.

Coolant Temp Switch(on intake under FPR)

.3053190

 

Coolant recovery reservoir

25525470

.

Crank Shaft, GN/T-Type

12350247

.

Crank Shaft, Turbo Trans-AM (Same as above but has cross drilled main journals)

25535742

.

Crankshaft Balancer Spacer "seal" .030" (max. .060")

25523377

.

Crank Sensor (Complete)

25525667

.

Crank Sensor Bracket

12537113

(AC/Delco #213-280)

Crank Sensor Bolt

12537114

(AC/Delco #213-281)

Crank Sensor

12537109

(AC/Delco #213-292)

1986 ESC Module

16022614

.

1987 ESC Module

16051654

.

Cam Sensor With Drive

25516915

.

Cam Sensor

25518357

.

Cam Sensor Shaft O Ring

1959331

.

Cam Sensor Spacer Shims

1837617

.

EGR filter

10159525

.

EGR Valve

17111570

 

ECM

1227148

.

Engine, Short Block minus cam

25527476

List $1575 on 6-91 Discontinued

Exhaust Turbo Outlet Pipe (Downpipe)

25526459

.

Exhaust Catalytic Converter

25103338

.

Exhaust "Y" Pipe After Converter

25525383

.

Exhaust Pipe Over Axle LH

25520013

.

Exhaust Pipe Over Axle RH

25520012

.

Exhaust Muffler

25520009

.

Exhaust Tail Pipe LH

25520011

.

Exhaust Tail Pipe RH

25520012

.

Exhaust Manifold LH

25527391

.

Exhaust Manifold RH

25527378

.

Exhaust, Catalytic Converter Hanger

25525381

.

Fan delay relay

25527402

.

Fan Hi and Low Relay

25526984

.

Passenger Side Relay Shroud

25518460

.

Flexplate Turbo 81-87 (heavier piston/pins)

25512350

.

Fuel pressure regulator, Turbo TA and Somerset

25523720

.

Fuel Rail

25524302

.

Fuel Rail, Feed Line (Pipe Assembly)

25526146

.

Fuel Injector O Ring

10031124

.

Fuel Injector Wire Harness

12060425

.

Fuel Pump Strainer Sock

25055458

.

Fuel Line 'O' Rings Return line at FPR .

22516256

 

Fuel Line 'O' Rings Feed line at fuel rail

22514722

 

Fuel Meter Gasket (Between Sender and Tank)

12337247

.

Fuel Pump Relay

10038490

.

Fuel Pump Hanger/Sender

9167390510

.

Gasket Kit, Engine Overhaul (Contains all engine gaskets EXCEPT valve seals)

12328748

.

Gasket Kit, Top End (Includes head gaskets, intake gasket, and valve cover gaskets)

12328759

.

Gasket kit, Front cover (Includes cover gasket, water pump gasket, mechenical fuel pump block off plate gasket. This kit will also fit Buick 3.0L FWD V6)

12337540

.

Gasket, Oil Pan

25521994

.

Gasket, oil pick up screen to block

24501259

.

Gasket, Head gaskets (composite)

25528486

.

Gasket, Head gasket (steel shim)

25524599

.

Gasket, EGR to intake $1.14

25530599

.

Gasket, IAC (round)

25530697

.

Gasket, Upper Plenum to Intake

24502089

.

Gasket, Throttle-Body to Upper Plenum

25517008

.

Gasket, Turbo Inlet bell

25514608

.

Gasket, Vacuum block (top of throttle body)

25536028

.

Gas tank, with TR baffle

22523080

.

Governor (transmission)

8655976

.

Grommet, Pass Side Valve Cover

1264486

 

Heater hoses Inlet

25525213

.

Outlet

25525214

.

To water pump

25525228

.

Water pump Bypass

25525245

.

Idle Air Control (IAC)

25527077

 

Ignition module

25526449

.

Intake Manifold

25527221

.

Intake, Upper Plenum

25525146

.

Knock Sensor

10456287

 

Lifter Set

5234485-12

.

Low fuel warning assembly

6432974

.

Mass air flow sensor

25007866

Discontinued

MAF Sensor (3"Impalla SS)

25180303

(AC/Delco 1#213-352)

Motor Mounts Left

1255273

.

Right

1255274

.

Oil Cooler Adapter

25530885

Discontinued

Oil Cooler Adapter O Ring

25530999

.

Oil Pressure Switch

25036378

 

Oil Pressure Switch Molded Connector

12085529

(has 3 white wires which need to be spliced in)

Oil Pump, stock

12337732

.

Oxygen Sensor, (Stock)

25162693

(AFS-20)

Oxygen Sensor, (GNX)

25162753

(AFS-22)

Oxygen Sensor, (GM) Heated

25312179

(AFS-74)

Oil Supplement, GM Engine (EOS)

1052367

.

Posi Traction Additive

1052358

.

Posi, Clutch Pack

00231127

.

Positive Battery Cable

12157883

.

PCV valve

25095468

AC# CV893C

PCV grommet

1381487

.

PCV hose

10055808

non turbo part that works-must cut to fit

PCV hose Dayco

87000

3/8" hose with a 90 degree bend that can be trimmed

Push Rod, Stock

25510025

.

Radiator hose Upper

25525229

.

Lower

25523616

.

Radiator Cap

RC27

.

Seal, Intake Valve (no seals used on exhaust valves)

25535162

.

Servo Cover (Transmission)

24200798

.

Starter, Light Weight Unit

10465293

(95+ F-bodies w/v8) AC/Delco # 323-488

Starter, Bolts for Light Weight Unit above

12338064 & 14037733

.

Switch, Hobbs GM

25503871

.

Throttle Position Sensor (TPS)

25036663

 

Timing Chain Tensioner

25532546

 

Timing Chain Tensioner Spring

1358909

 

Transmission Dipstick grommet

1259475

.

Transmission Valve Body Separator Plate

8657309

.

Top Engine Clean

1#1050002

.

Throttle Valve Cable

25532115

.

Torque Converter Clutch Solenoid

8639900

.

Turbo Inlet Gasket - Rivera

1261269

.

Turbo oil drain gasket

25537227

.

Turbo to downpipe seal

1262500

.

Turbo center housing rotating assembly

25527601

.

Valve Body Separator Plate

8657309

.

Vacuum Block Assembly (TTA)

25536304

 

Vacuum Check Valve (one way)

14047619

.

Vacuum Check Valve HVAC/Cruise

14056648

 

Valve, Check

25525315

.

Valve Stem Umbrella Seal Kit

12511890

.

Valve Springs, LT1 ~105# Seat Pressure

3927142

.

Valve Cover Grommet (passenger side)

1264486

.

Wastegate - adjustable

25527603

.

Wastegate control hose assembly

25525576

.

Wastegate solenoid

1997157

.

Wastegate solenoid filter

801528

.

Non GM parts

 

.

Alternator bearing/ Idler pulley

6203LU

.

Axle Housing gasket (rear end cover)

 

 

Engine Dynamics (McCord)

DT004

 

FelPro

RDS55028-1

 

McCord

762060

 

Victor

P27857

 

Larger rear brake cylinders GM

18012305

.

EIS

104432

.

Bendix

#WC37644T

.

Brake, Speed Bleeders (Russell) front

3958

Summit

rear

3952

.

Brake, PowerMaster (AutoZone)

52-9702

Autozone rebuilds

Brake, Proportioning Valve (Adj.)

G3905

Summit

Converter, Vigilante

239028-7

(0#)~32-3500 rpm stall, 7-disc

Coolant Temp Sensor F.A.S.T.

30-7003

 

Coil Pack, GM/Magnavox(Accel)

140016

.

FelPro Gaskets

 

.

Axle Housing (rear)

RDS55028-1

 

Conversion Set 3.8l

CS 8142-4

20 bolt oil pan, VIN A, 7, 9

Distributor Mounting "O" Ring

1-420

.

Timing Cover Packing

1-3986 AF

.

Fuel Pump Mounting

1-5181-1

.

Rear Main Bearing Cap Pin

2-10675 S

.

Oil Pressure Relief Valve

1-11927 C

.

Rear Bearing Cap Seal

2-12708

.

Rear Bearing Cap Pin

2-12708 S

.

Water Pump

1-12996-1

.

Oil Pump Suction Flange

1-12999

.

Rear Main Bearing Seal

2-13044 AF

.

Timing cover

1-45006-1

.

Oil Pump Cover

1-70032

.

Oil Pan Drain Plug

1-70822

.

Oil pan (Perma-Dry molded rubber)

1-90161

.

Timing Cover Set [Replaces #12337540]

TCS45930

Timing cover #95364, O-ring #420, fuel pump #5181,water pump #12996, oil pump cover #70032

Oil Pan Set [Replaces #25521994]

OS30521R

oil pan #90161, oil pickup #12999

Intake Manifold Set [Replaces #12328760]

MS96033

intake manifold #96033, end seals #90911, O-ring #420, vacuum block #94210,RTV#226L

Valve Cover Set

VS50156C

.

ROL Oil Pan Set (cork)

0S5755

.

Felpro Gaskets Exhaust

1400

.

Felpro Gaskets Intake

1200

.

Felpro Gaskets Head (3.8)

1000

.

Felpro Gaskets Head (4.1)

1026

.

Felpro Gaskets Head (Wire-loc)

1007

.

Main seal kit

BS40613

.

Head Gasket set - for vin 7 3.8L

HS 9441 B

.

water outlet "O" ring

1-427

.

Head gasket

2-9441 B

.

Valve Cover

2-50156

.

Throttle Body

1-60654

.

Throttle Body

1-60656

.

Valve Stem seal (VITON)

6-70817

.

EGR

1-72635

.

Fuel Feed Seal

4-90457

.

Fuel Return "O" Ring seal

4-90467

.

Exhaust Manifold

2-90508

.

Oil Drain Connector

1-90587

.

"O" Ring Fuel Injector seal

7-92588

.

Intake Manifold Plenum

1-93332

.

Oil Cooler

1-93378

.

Vacuum block

1-93979

.

Turbo Exhaust Seal

1-60755

.

Clevite Bearings (See Note 1)

 

.

Cam Bearings

SH1376S-XX

.

Rod Bearings

CB1398H-XX

.

Main Bearings

MS960H-XX

.

Cyberdyne Air/Fuel gauge

7009

.

O2 sensor - 3 wire - F.A.S.T

30-7001

 

Manifold Air Temperature Sensor - F.A.S.T

30-7004

 

Pistons, TRW Forged (See Note 1)

L2481F-XX

.

Piston Rings, Sealed Power, Plasma Molly, FILE TO FIT (See Note 1)

R-10437-XXX

.

Piston Rings, Sealed Power, Molly, NON-FILE TO FIT (See Note 1)

E-434K-XXX

.

Piston Rings, Gapless Total Seals ( standard )

TSR-2165TS1

.

Piston Rings, Gapless Total Seals ( 0.030 over )

TSR-2165030TS1

.

HD Billet Servo Slide Assembly (SSA) 200-4R

20040

Fairbanks Racing Products

Rocker Arm, Shaft HD

RS-624

(Sealed Power)

Rocker Arm, Shaft HD Assembly

RA-1068H

(Sealed Power)

Thermostat 160 (Motorcraft )

RT-350

 

Thermostat 160 (O; Rielly)

13356

 

Thermostat Gasket

 

 

 

25132

 

Valve, Springs:

 

.

OD(in.)

Closed#

Open#

Rate(#/in.)

Part number

1.20

80

200

267

VS677

1.23

85

230

295

VS1615

1.264

105

277

350

VS739R

1.24

80

200

267

CC 979

1.23

91

229

307

CC 980

1.25

105

295

423

CC 981

 

Federal Mogul and Comp Cams numbers. CC979 has no internal dampers.

Posi Unit, Moroso Brute Strength

83030

.

Timing Chain, Cloyes True Roller

93134

.

Higher Capacity Oil Filters

 

.

AC

PF-52

.

Fram

3980

.

Mr Gasket Universal Drain Plug Kit

GKT 4470

.

O2 Sensors, Bosch One wire

0-258-002-019

.

Three wire

0-258-003-106

.

Fuel Injector O rings (Also for regulator)

SK1 RN7

.

Fuel Injector, "Blue Tops"

0-280-150-967

.

K & N Filters Stock Replacement style

RE-0910

.

Main Stud kit for Buick V6 Stage 1 & 2, 2-Bolt Main, includes nuts and washers.

123-5401

ARP

Valve cover vent

62-1160

.

B&M Transkit for THM200-4R

35229

.

B&M Supercooler (11" x 7")

70255

.

Transmission filter and pan gasket set Fram

1057B

.

Relay, 30 amp, for Fuel pump hot wiring, Radio Shack

275-226

.

TCI Filter and Pan Gasket Kit

386500

.

TCI Pro Super 200-4R Overhaul Kit

386800

.

TCI Hardened Input Shaft

384500

.

Coolant Temp Sensor Speed Pro Electronics

30-7003

.

3-wire O2 sensor Speed Pro Electronics

30-7001

.

Manifold Air Temp Sensor Speed Pro Electronics

30-7004

.

TCI TR calibrated valve body (BRF equivalent)

382200

.

Stock Replacement Oil Pump Kit, Melling NAPA#

BK601-1311

.

Southside Machine Lift Bars

P1313

.

Jacobs Spark plug wires

401290

.

Valves, Intake (TRW)

V3124X

1.770"

Valves, Intake (Manley) Severe Duty

11502

1.710"

Valves, Exhaust (Manley)

11503

1.500"

Valves, Intake (Manley) Severe Duty

11504

1.775"

 

Convert Your 84/85 to an 86/87 ECM

Benefits

The following article describes how I updated my wiring harness and ECM to the newer '86-87 ECM. This update has several advantages over the original ECM such as:

  • Greater chip availability
  • The ability to use Tweaker to program you own chips
  • Twice the available data from TurboLink (R) in Road Mode
  • The ability to use BST-001 Boost sensing option for TurboLink (R)
  • 1227148 ECM's are readily available in the "yards"
  • Electric fan control available (Optional)

I'm sure there are more reasons to change to the newer ECM, but these are the major reasons, feel free to think up your own too. <grin> I have received a lot of e-mail from people wondering if the car will run faster or get better ET's from the conversion. None of this will happen UNLESS it stems directly from the advantages listed above.

Limitations

A few things the ECM conversion won't do is to:

  • Make a poor running car run better
  • Fix a broken fuel pump
  • unplug a fuel filter
  • Repair bad injectors
  • Fix a bad TPS
  • Fix a bad CTS
  • unplug a plugged cat converter

The Conversion

After much testing, I must suggest that you also get a 86/87 MAF part #25007866. The calibration of the 84/5 MAF is different and gave drivability problems with the 1227148 ECM, when cold weather came upon us in St.Louis. The colder air sensed by the MAT richened up the fuel air ratio, trying to compensate for the denser air, to the point that the car would belch black smoke out of the exhaust. Switching to the 86/7 MAF cured the problem.

First off I went to the U-Pullit and got a wiring harness out of a FWD GM car with a '86-87 3.0-3.8 V-6 in it. When I removed the wiring harness, I removed the relays and sensors that were plugged into it too. Then I striped the harness down and dissected it wire by wire. This way, I got all the fan relays AND the MAT sensor w/plug and wire to the ECM. The wires at the ECM plug come out with a large paper clip (or jewlers screwdriver) inserted into the release hole. If you have never had a wire out of the ECM plug before, I suggest a little practice on the OTHER harness first!

Before your car can be driven without the SES light on, the MAT sensor must be put in. I cut a hole in the bottom of the K&N right in front of the MAF sensor to sample the incoming air temperature. Then I took the sensor plug/wire and ran it to the ECM by poking thru the grommet on the speedometer cable. I use wire loom in the engine compartment to dress things up and make things look factory. I ran the wire to the ECM under the dash carefully staying away from the gas and brake pedals. The MAT uses the same sensor ground as the TPS and CTS ,so I spliced into the ground wire at the ECM (D-12 black,no stripe). The other wire from the MAT sensor needs to be plugged into pin #C-11 (tan) at the ECM, this is where the wire from the other car came into play. It should still have the clip on the end that will plug straight into C-11 on the ECM plug.

The ECM can come out of a 86 century but be sure to have the part #1227148 ECM. The dealer gave me two part #'s for the cal-pak in the ECM, they are 16036503 and 16036504. My 84 ECM HAD the 16036504 in it so I used it.

Pitch any other cal-pak with a different number. I downloaded a ROM file from the archives for the prom. Any 86-7 chip should do. Use a stocker to get things going. But with the addition of the MAT sensor, and the chips to the ECM, this will plug straight in and run.(without the MAT sensor)
As far as the electric fan setup goes, This IS an option. The fan control at the ECM is pin #D-2. This circuit grounds a relay when active. There are many ways to wire and electric fan. So I will not go into too much on it right now. I wired up the 10 min timer to come on if the car shuts off and the temp sensor in the radiator is tripped (about 195 deg) with the fan on high. The fan also runs on hi when the ECM calls for it. I have the low speed coming on with the A/C. To get more acquainted with the fan circuit (and ECM) I went to the library and looked up all the different years in the Mitchell manual. Take a bunch of dimes and copy the pages that you are interested in, like the ECM pinout and the fan setup on several cars. I found some pusher/puller fan setups too.

As you should always do when splicing/adding wires. I use a 150 watt or so soldering gun and rosin core electrical solder to solder ANY connections you make. There is nothing more frustrating than looking for an electrical "gremlin" than to find out that YOU were the cause of it by not doing it right the first time. Get the wire good and hot so the solder can flow into it.

Also use HEAT SHRINK! Tape tends to come loose and fall off over a period of time, and get "gooey".

At the ECM , taking the wire out of the plug , stripping a small area bare a couple of inches from the plug and solder the wires together. Then, slip on the heat shrink, and make sure it shrinks good.

By following my procedures outlined here, the ECM can be changed (less fan circuit) in about 30 minutes if you have all the stuff already.

 


 

Production 3.8 Liter Turbo Timing Cover

Casting number


REAR

DETAIL

Features of Note:

  • Water pump openings on the left and right
  • Aftermarket Neoprene front crank seal is installed on this cover
  • Cam Sensor is installed in this view. Notice how it meshes with the Oil pump shaft
  • Oil pump passages (3 round holes on the lower right)
  • Cast aluminum

Features of Note:

  • Water Pump is installed already in this view
  • Pressure Relief Valve, Spring and Cap are shown
  • One oil pump gear rides on a dowel cast into the front cover (not visible in this view)
  • Oil cooler adapter uses the O ring for sealing between the oil filter and oil pump body.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Production 1984-1985 Turbo 3.8 Liter Intake

Casting number 25515926

 

TOP

SIDE

Features of Note:

  • From the top you can see the PCV hole with grommet on one side and the turbo oil drain with grommet on the other side.
  • The intake uses the older style thermostat like a SBC (left side of picture)
  • Turbo inlet is on the right side of the picture

Features of Note:

  • From the side you can see decent sized intake ports
  • You can see the "low rise" intake runners and central plenum area.

BOTTOM

TURBO INLET

Features of Note:

The bottom of the intake shows some of the flow pathAir enters the intake flows to the front of the intake and turns back and is distributed to the intake runners.

Features of Note:

The intake hole for the turbo is split directing the flow to the right and left separately with the EGR port in the middle.

You can see where the EGR port comes through the intake from the head, it is directed to the turbo inlet through the valve and pipe(not pictured) to a large threaded hole on the side of the turbo inlet port on the intake

BACK

FRONT

Features of Note:

  • This view clearly shows the turbo inlet
  • You can see the grommets for the oil return and EGR

Features of Note:

  • This view clearly shows the larger thermostat opening.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Production 1984-1985 Turbo 3.8 Liter Intake

Casting number 25515926

 

TOP

TURBO MOUNTING

Features of Note:

  • This is a view of the unique way that the oil return runs on an '84/85 turbo setup.
  • Arrow points to grommet in the intake that the oil return pipe plugs into

Features of Note:

  • In this view you can see the oil feed line (bottom/center of picture
  • The throttle body is to the right of the picture.
  • It's a TIGHT fit for the turbo in this mounting position!

MOUNTING

TURBO INLET

Features of Note:

Turbo inlet adapter plugs into the large hole (white arrow)

Green arrows indicate mounting points for the turbocharger itself

Features of Note:

  • This shows the oil return pipe
  • Notice the 'bellows' to allow some flex and expansion

 

 

 

 

 


Stock 1984-1985 Turbocharger

Stock

BOTTOM

FRONT/COMPRESSOR

 

 

Features of Note:

  • This is a stock "Hot Air" turbo
  • Notice the O ring on the compressor outlet. This friction fits into the intake manifold
  • If you look closely, you can see the smallish sized turbine wheel
  • Exhaust housing is very similar to later turbos

Features of Note:

  • From this angle you can see the much smaller diameter of the compressor housing compared to the 86/87
  • The turbine housing also looks to be a tighter scroll
  • Notice the way the wastegate actuator pressure feed is at the back of the scroll

 

 

INSIDE COMPRESSOR

BOTTOM/TURBINE

 

 

Features of Note:

This is an interesting view of the inside of the compressor housing

Notice the oil residue...evidently the compressor seal on this particular turbo was leaking The compressor inlet hole is pretty small Again, you can see the O ringed adapter piece that fits into the intake manifold

Features of Note:

Notice the turbine scroll is "fatter" and smaller than the '86/87

This shows the separate inlet adapter with the O ring pretty clearly

This is the bottom of the turbo and you can see the oil return, which is pretty standard

 

CENTER SECTION

TOP

 

 

Features of Note:

  • The center section looks very much like any other Garrett turbo
  • Notice the oil feed fitting on the right/center of the picture
  • The turbo support bracket bolts to the turbine housing
  • This view shows how "fat" and tight the scroll is for the turbine side

Features of Note:

  • The fitting is the oil feed line
  • This view shows pretty clearly how small the compressor is
  • The smaller compressor housing can fit the tight space at the back of the motor under the hood

 

COMPRESSOR

EXHAUST/TURBINE

 

 

Features of Note:

  • This view shows how "fat" and tight the scroll is for the compressor side
  • Notice the standard inlet bell (bolt on style)

Features of Note:

  • Notice the small size of the wastegate hole
  • Notice the smallish turbine hole

 

 

 


 

Fuel Injection ECM Pinouts

Scott Simpson

1986 & 1987 3.8 Liter Turbo Engine

This ECM Chart is for use with a digital voltmeter to further aid in diagnosis. The voltages you get may vary due to low battery or other reasons, but should be close. The ECM has 2 connectors: 1 24-pin (A&B) and a 32-pin (C&D)

The following conditions must be met before testing:

  • Engine at operating temperature, Diagnostic terminal not grounded,
  • Idling in closed loop (for "Eng. Run" column), ALDL tool not installed.

Key On

Eng. Run.

CIRCUIT

PIN

WIRE

0*

B+

Fuel Pump Relay

A1

Green/Black

B+

0*/B+

A/C Clutch Control

A2

Light Green/Black

B+

B+

Canister Purge Control

A3

Green/Yellow

B+

B+

EGR Control

A4

Grey

0*

B+

"SES" Control

A5

Brown/White

B+

B+

IGN-ECM Fuse

A6

Pink/Black

B+

B+

TCC Control ALDL

A7

Tan/Black

4.3

varies 2-5

Serial Data ALDL

A8

Orange

5.0

5.0

Diagnostic Term ALDL

A9

White/Black

0*

0*

Speed Sensor Signal

A10

Dark Brown

0*/B+

B+

Cam Hi

A11

Black

0*

0*

Ground

A12

Black/White

.

.

Not Used

B1

.

.

.

Not Used

B2

.

0*

0*

Crank Reference Low

B3

Black/Red

0*

0*

EST Control

B4

White

0*/B+

B+

Crank Reference High

B5

Purple/White

2.50

2.48

MAF Sensor Signal

B6

Yellow

8.71

8.75

ESC Signal

B7

Yellow/Black

B+/0*

B+/0*

A/C Signal (On/Off)

B8

Light Blue

.

.

Not Used

B9

.

0*

0*

Park/Neutral Switch

B10

Orange/Black

.

.

Not Used

B11

.

B+

B+

Injector #5

B12

Black/White

.

.

Not Used

C1

.

.

.

Not Used

C2

.

N/U

N/U

Idle Air Control B Lo

C3

Green/Black

N/U

N/U

Idle Air Control B Hi

C4

Green/White

N/U

N/U

Idle Air Control A Hi

C5

Blue/White

N/U

N/U

Idle Air Control A Lo

C6

Blue/Black

0*

0*

3rd Gear Signal

C7

Green/White

0*

0*

4th Gear Signal

C8

Light Blue

.

.

Not Used

C9

.

2.04

2.18

Coolant Temp. Signal

C10

Yellow

2.46

2.09

Mass Air Temp. Signal

C11

Tan

B+

B+

Injector #6

C12

Black/Yellow

.36-.44

.36-.44

TPS Signal

C13

Dark Blue

5

5

TPS 5 volt Reference

C14

Grey

B+

B+

Injector #2

C15

Black/Green

0*

0*

Battery 12 volts

C16

Orange

0*

0*

Ground

D1

Black/White

B+

B+

Low Speed Fan Control

D2

Dark Green

B+

B+

Wastegate Control

D3

Pink/White

.

.

Not Used

D4

.

4.56

4.56

Bypass

D5

Tan/Black

0*

0*

O2 Sensor Ground

D6

Tan

0*

0*

O2 Sensor Signal

D7

Purple

.

.

Not Used

D8

.

0*

0*

EGR Diagnostic

D9

Purple/White

0*

0*

Ground

D10

Black/White

.

.

Not Used

D11

.

0*

0*

TPS/CTS/MAT Ground

D12

Black

.

.

Not Used

D13

.

B+

B+

Injector #1

D14

Black

B+

B+

Injector #3

D15

Black/Pink

B+

B+

Injector #4

D16

Black/Red

Notes:

  • B+ Battery Positive voltage
  • * Less than 1 volt
  • 1. VSS varies from .45 to B+ depending on speed
  • 2. CTS at Normal Operating Temperature
  • 3. A8 & D7 varies
  • 4. A1 is B+ first two or three seconds
  • 5. A11 & B5 Depends on vane position in relation to "hall effect" switch. Voltage is low when vane is passing through switch.
  • 6. A2 & B8 Engine running, voltage will be high or low, dpending on whether A/C is on or off.
  • 7. N/U is Not Useable

 

 


 

Cam Sensor Frequently Asked Questions

Tom Chou 

Cam Sensor Basics

If we're discussing a DIS on a TR, well after 10 years I'm surprised there's still confusion.

1.

Setting the cam sensor has NOTHING to do with initial timing.

2.

Moving the cam sensor a few degrees does nothing to the ignition timing. If the car runs, (and the 3x trigger on the balancer is mounted correctly by the factory) then your ignition timing will be EXACTLY what's in the spark map of the chip regardless of where the cam sensor is set.

3.

I say if the car runs, because for ignition timing, all the cam sensor does is tell us which cylinder is #6. After the cam signal goes LOW, (stock spec is 25 deg ATDC of cylinder #1) the next RISING edge of the CRANK pulse will occur exactly 10 deg BTDC of cylinder #6.

4.

Therefore, if the cam signal wasn't there, you would never know which crank pulse signaled #6 (or any other cylinder for that matter).

5.

Once we have this info, cylinder #6 and #3 will fire. Remember this is a waste spark system (but I'm sure everyone knows that by now) so #6 will be on compression but #3 on exhaust, whose spark is wasted. It takes very little energy to fire a plug that's not under compression, so it's no big deal.

5a.

Note also that the current goes through and fires one plug the "normal" way (center electrode to GND electrode), through the block, and fires the other plug "backwards" (GND electrode to center electrode).

5b.

This being the case, if you switch wires on the SAME coil (6&3, 1&4, 2&5) it won't make a bit of difference to the car - the plug that was "backward" firing before will now be "normal" and vice versa.

5c.

So you can see, on crank up and during limp-home mode, spark advance is 10 deg BTDC since the rising (active) edge of the crank signal occurs 10 deg BTDC of every cylinder.

6.

So, moving the cam sensor within the window where the next rising crank pulse is the #6 cylinder has absolutely NO effect on actual ignition timing. Ignition timing calculations are based off the CRANK sensor, which cannot be adjusted short of modifying the balancer or retapping the crank sensor mounting location!

7.

So what happens when you move the cam sensor beyond that window and the next crank pulse is either #1 or #5 (depending on the direction you moved it) and not #6? You guessed it, the #6/3 coil will still fire, but the #6 won't be anywhere near TDC and the engine will either kick back or just not run. Regardless, if you get the cam sensor out of adjustment enough to affect ignition timing, it'll simply be out of sync so much the car won't run. That's why if the car is actually running, you can bet the ignition timing is dead on.

8.

This brings up some more points. (Might as well be thorough) What happens if you set the cam sensor 180 degrees out? For ignition, nothing. The plug that was supposed to be on compression will now be on exhaust, and vice versa. The car doesn't care! Ignition will be perfect. Fueling, on the other hand, is a different story. More on that later.

9.

What happens if you unplug the cam sensor while the engine is running? Nothing. A malf code will set, but as long as you don't kill the engine it'll keep running perfectly (assuming the crank sensor is good.) Once you kill it though, it won't start again.

10.

What happens if you move the cam sensor while the engine is running? Every two revs, the cam sensor info is checked. If the cam sensor signal is present, it updates and resyncs. If not there, a malf code is set and the previous sync is used. See #9. For ignition, moving the cam sensor within that window where it syncs correctly does nothing. Move it outside that window and you'll backfire like never before, as you'll fire the wrong cylinder at the wrong time. Trust me, I had it happen. My cam sensor lost it's tab for the keyway on the shaft and started moving on it's own. Exploded my mufflers. I wrote a note about 2 months back about that.

11.

So, I hope everyone's convinced that adjusting the cam sensor has absolutely no effect on ignition timing, but can only cause a no-start or tremendous backfire & stalling if running.
A stretched/slipped timing chain therefore also has no effect on ignition timing.

12.

HOWEVER, adjusting the cam sensor has a tremendous effect on FUELING, as the SFI syncs off the cam too. I don't know much (yet) about the fueling specs, but it apparently has a much narrower window than ignition in order to sync to the wrong cylinder. This is why if you have the cam 180 deg out the car will run terribly because the fueling is all messed up. Basically it'll be in a SFI mode where fuel is puddling for 1 rev before being sucked in.

13.

This is where any performance gain/losses will occur. MAYBE advancing the cam sensor a bit might help a big cam engine that opens the intake sooner, I don't know.
It definitely affects idle quality having the cam sensor out of adjustment. In my opinion I can't see how advancing the cam will help as you're practically in a batch fire mode at WOT where the injector is on practically the whole time. I can't see how a few msec sooner is going to have a great effect. SFI has it's greatest effect at idle & part throttle, and a misadjusted cam definitely can be felt here.
Actually, the fueling can only sync off the crank signal too, with the cam telling it which crank pulse corresponds to which cylinder, so it you're off, you're off by a whole cylinder. It'll be a step function. Within a certain window, you'll be fueling the same cylinder, adjust some more, and you'll step into another one. I can't believe fueling the wrong cylinder can help performance no matter what cam you have.

14.

I think that's it. Sorry, didn't mean to write a book. Isn't this info in the FAQ list or something? If not it needs to be. Too much misinformation out there. I should copyright this and charge! Now that it's posted on the list, everyone will be an expert on this and can claim "Oh yeah, I knew that stuff 10 years ago!" Yeah, right. But that's what this list is for, to educate Buick owners and admirers about their cars, so that they don't get ripped off by mechanics and such, right Scott?


 

C3I Ignition Module Swap for '84/85 Turbo Regals

David A. Arieno

C3I Ignition Module Connector Pin Out for using an '86/87 Module on an '84/85 Turbo Regal

IMPORTANT!!

Study the attached "pin out" chart for '84-'85 C3I connector. Mark the current wires, (using small strips of masking tape), with their description and wire number! (You'll be amazed how much easier it'll be if you do!!!)

  1. Gently pry the weather seals loose from the connector, sliding them down the harness approximately 2". Using a suitable pin removal tool, remove required metri-pack pins, pulling them forward through the connector. (Remember, pins "A", "B", and "C" remain the same, and don't need to be removed.)
  2. I recommend that you purchase 15 or more new metri-pack pins (NAPA # 725189, 25 pins to a pack; also available through GM and Belden)
  3. Remove pins from the wires. (Snip the wires as close to the pins as possible! )Pull the wire back through the connector and weatherseal.)
  4. Arrange the wires as required and push them back through the rubber weather seal.(These hold seven wires each, and actually help hold things in proper order while you are reinstalling the pins).
  5. Starting with pin "D" strip approximately 1/16" off the wire, and pull it through the metri-pack connector.
  6. Carefully crimp the two rear tabs of a new metri-pack pin over the end of the insulation, then lightly solder the pin to the exposed copper wire. Gently crimp the remaining tabs over the solder joint.(Yes, it's a crimp type pin, but solder it anyway! It ensures you have the proper connection)
  7. Gently pull the wire back into the metri-pack connector, ensuring that you have the
    pin positioned properly. This should lock the pin into the connector.
  8. Repeat with remaining pins.
  9. Gently slide the weather seals up the wires toward the connector and push them into the connector. That should do it, clean and neat! I leave up to you to fabricate a suitable adapter mount plate. Start with a 4.5" by 6" piece of 1/16" plate.......

Alternate Method

-VERY IMPORTANT! -MARK ALL WIRES TO THE IGNITION MODULE CONNECTOR WITH TAPE.
Cut the wires on the harness outside metri-pack connector and splice the harness back together with shrink-butt crimp connectors. Soldering and heat shrink would also work.....
BE CAREFUL! The harness wire length doesn't leave you much room for error.

  1. Pin A: This pin remains the same. ("ECM B4 EST", white wire, #423)
  2. Pin B: This pin remains the same. ("ECM D5 BYPASS", tan/black wire, #424)
  3. Pin C: This pin remains the same. ("ECM B5 REF. LOW", purple/white wire, #430)
  4. Pin D: Remove "TACH LEAD" (white wire, #121). Splice in "ECM B-3 REF. LOW", black/red wire, #453. [Previously located at pin F position!]
  5. Pin E: Remove "ECM ALL CAM" (yellow wire, #951). Splice in "TACH LEAD",white wire, #121. [Previously located at pin D position!]
  6. Pin F: Splice in" CRANK SENSOR B", green wire, #918 [Previously located at pin G position!]
  7. Pin G: Splice in "CRANK SENSOR C GRND", black wire, #952. [Previously located in pin H position!]
  8. Pin H: Splice in "CRANK SENSOR A 12V", white/red wire, #916. [Previously located in pin J position!]
  9. Pin J: ( Pin I not used.) Splice in "ECM ALL CAM", yellow wire, #951. [Previously located in pin E position!]
  10. Pin K: Splice in "CAM SENSOR B SIGNAL", blue lt wire, #917. [Previously located at pin L position!]
  11. Pin L: Splice in "CAM SENSOR C GRND", black wire, #952. [Previously located at pin K position!]
  12. Pin M: Remove "CAM SENSOR A 12V", white/red wire, #916. Splice in"IGNITION POWER", pink/black wire, #839. [Previously installed in pin P position!]
  13. Pin N: Remove "IGNITION POWER", pink/black wire, #439. Splice in "CAM SENSOR A 12V", white/red wire, #916. [Previously installed in pin M position!]
  14. Pin P: (Pin O not used.) Splice in "IGNITION POWER", pink/black wire, #439. [Previously located in pin N position!] That should do it! Plug it in, tighten it up, time for an ops check!!!!!!

1984-85 Turbo Regal C3I Ignition Module Connector Pinouts

PIN

WIRE #

DESCRIPTION

WIRE COLOR

A

423

ECM B4 EST

WHITE

B

424

ECM D5 BYPASS

TAN/BLACK

C

430

ECM B5 REF. HIGH

PURPLE/WHITE

D

121

TACH LEAD

WHITE

E

951

ECM ALL CAM

YELLOW

F

453

ECM B3 REF. LOW

BLACK/RED

G

918

CRANK SENSOR B SIGNAL

GREEN

H

952

CRANK SENSOR C GRND

BLACK

J

916

CRANK SENSOR A 12V

WHITE/RED

K

952

CAM SENSOR C GRND

BLACK

L

917

CAM SENSOR B SIGNAL

BLUE LT

M

916

CAM SENSOR A 12V

WHITE/RED

N

439

IGNITION POWER

PINK/BLACK

P

839

IGNITION POWER

PINK/BLACK

1986-87 Turbo Regal C3I Ignition Module Connector Pinouts

PIN

WIRE #

DESCRIPTION

WIRE COLOR

A

423

ECM B4 EST

WHITE

B

424

ECM D5 BYPASS

TAN/BLACK

C

430

ECM B5 REF. HIGH

PURPLE/WHITE

D

453

ECM B3 REF. LOW

BLACK/RED

E

121

TACH LEAD

WHITE

F

643

CRANK SENSOR B SIGNAL

BLUE/WHITE

G

642

CRANK SENSOR C GRND

BLACK

H

641

CRANK SENSOR A 10V+

BLACK/LT GREEN

J

630

ECM ALL CAM

BLACK

K

633

CAM SENSOR B SIGNAL

BROWN/WHITE

L

632

CAM SENSOR C GRND

BLACK/PINK

M

639

IGNITION POWER

PINK/BLACK

N

631

CAM SENSOR A 10V+

YELLOW

P

439

IGNITION POWER

PINK/BLACK

TURBO REGAL C3I IGNITION MODULE CONNECTOR PIN OUTS (CONTINUED)

HYBRID '84-'85 HARNESS CONNECTOR
USING '86-'87 IGNITION MODULE

PIN

WIRE #

DESCRIPTION

WIRE COLOR

A

423

ECM B4 EST

WHITE

B

424

ECM D5 BYPASS

TAN/BLACK

C

430

ECM B5 REF. HIGH

PURPLE/WHITE

D

453

ECM B3 REF. LOW

BLACK/RED

E

121

TACH LEAD

WHITE

F

918

CRANK SENSOR B SIGNAL

GREEN

G

952

CRANK SENSOR C GRND

BLACK

H

916

CRANK SENSOR A 12V

WHITE/RED

J

951

ECM ALL CAM

YELLOW

K

917

CAM SENSOR B SIGNAL

LT BLUE

L

952

CAM SENSOR C GRND

BLACK

M

839

IGNITION POWER

PINK/BLACK

N

916

CAM SENSOR A 12V

WHITE/RED

P

439

IGNITION POWER

PINK/BLACK

 

 

 

 

 

 

 

 

 

IAC Reset Procedure with a Scan Tool

Ken Mosher

Procedure

The ECM controls idle rpm with the IAC (idle air control) valve. The idle rpm is programmed into the PROM. To increase idle rpm the ECM moves the IAC valve out allowing more air to pass by the throttle plate. To decrease rpm it moves the IAC valve in to reduce air past the throttle plate. A scan tool will read the ECM commands to the IAC valve in counts. Higher the counts the more the air is being allowed to pass the throttle plate (higher idle). Lower the counts the less the air is being allowed to pass the throttle plate (lower idle).

  1. Warm the engine to normal operating temperature. This is important ... the car needs to be in closed loop.
  2. Connect scan tool. Verify it's in closed loop.
  3. Put the car in park and wait a couple seconds for it to settle into a regular idle.
  4. Look at the IAC counts (# and not % in TurboLink™)
  5. If the IAC counts are between 10-40, then it's pretty close. Otherwise, do the following adjustment procedure, with a target number of around 20-25 counts.
  6. The Minimum Air adjustment screw is on the dirver's side of the throttle body on the throttle linkage arm (often times misunderstood as the "idle adjustment screw". Pull off the gray rubber cable protecting the screw head.
  7. Turn the screw in VERY small amounts (1/4 turn or so) to adjust the Minimum Air setting. Turning it counter clockwise closes the throttle blade and will normally raise the IAC counts. Turning it clockwise opens the throttle blade and will normally lower IAC counts.
  8. Carefully monitor the IAC counts while making small adjustments to the Minimum Air setting screw. Be sure to allow the car to "settle" a bit after each adjustment a couple of seconds.
  9. Once you have IAC counts adjusted to within your target range, adjust the TPS as described HERE.

 

Adjusting the TPS

Objective

To adjust the Throttle Position Sensor to recommended settings of between 0.40-0.46 volts at idle and between 4.5 and 4.8 volts at Wide Open Throttle (WOT). This procedure should be performed after the minimum idle air settings are already made (via the IAC reset procedure).

Equipment Needed

The following tools are needed:

  • Flat bladed screwdriver
  • Scan tool (alternatively, a digital voltmeter)

Procedure

  1. Hook up your scan tool where you can see the readings clearly from under the hood (alternatively, back probe the TPS blue wire with the positive lead of the meter and ground the meter's negative lead to the chassis or battery)
  2. Turn the key ON and leave the engine OFF
  3. Loosen the two screws on the side of the sensor (passenger side of the throttle body) enough to allow you to move the sensor in the "moon shaped" grooves.
  4. Grab the "nose" of the sensor (where the wires plug in) and pull the sensor as far forward as possible and snug the screws enough that it holds the sensor in place (but can still be moved if nudged)
  5. Check the idle reading and tap the nose of the sensor up or down until you get an idle reading of between 0.40 and 0.46 volts. Anything above about 0.5 volts will not be seen as "idle" by the ECM and can cause driveability problems.
  6. Snug the screws down tight enough that the sensor doesn't move and have someone floor the throttle (make sure that the floor mat is out of the car...)
  7. Check the reading and adjust until the sensor reads between 4.55 volts and 4.85 volts. The intent is to make sure that the reading is high enough that the ECM reads full WOT. The actual number doesn't really matter as long as it is with the range.
  8. Recheck the idle reading to make sure that it hasn't changed. This can be a bit of a balancing act and require some very small adjustments and several iterations before both the high and low settings are where you want them to be.

Note: Occasionally a TPS will need the moon shaped grooves honed out a bit with a rat tail file to get enough adjustment, but normally the trick of moving the sensor as far forward as possible gives enough adjustment. Also, be very careful around the little roll pin that rests on the throttle lever, since it can bend or break.

 

 

Cam Sensor Adjustment Procedure

Cam Sensor Adjustment Procedure

1.

Measure on a piece of masking tape and mark it at 1.45" and tape it to the Balancer at 0 degrees.

2.

Bring #1 to TDC and then grab the intercooler fan and rotate the motor to your mark (25 degrees ATDC). This takes a little patience and muscle. You can try bumping it with the starter, but I'm never very successful at that.

3.

Back probe the middle wire of the cam sensor (marked B and normally blue) with a voltmeter. Turn the key ON, but leave the engine OFF.

4.

Loosen the sensor with a distributor wrench or a wobble socket and extension.

5.

Rotate the sensor full CLOCKWISE. The voltmeter should read 7.5+ volts.

6.

Slowly rotate the sensor COUNTER clockwise until the voltage drops.

7.

Secure the sensor at the instant the voltage drops.

The sensor is a hall effect device with a rotating metal ring that is driven from the front of the cam gear via a shaft (like a distributor). This ring passes thru a grooved sensor molded into the sensor cap. The metal ring has a notch or window cut out of it. When the window goes by the sensor, the voltage drops, which tells the ECM where #1 TDC is.

Jim Frankovich has done some measuring and calculating and has the following input:

  • 20º = 1.160"
  • 21º = 1.218"
  • 22º = 1.276"
  • 23º = 1.334"
  • 24º = 1.392"
  • 25º = 1.450"
  • 30º = 1.740"
  • Every degree figures out to be about 0.058"

Several people have found that when running a bigger cam with advanced valve timing, it sometimes will help cure a popping or sputtering symptom by advancing the cam sensor a few degrees. The above values give you an idea of what to shoot for.

 

Cam Sensor Information and C3I Module Pinouts

Cam Sensor Adjustment Procedure

1.

Measure on a piece of masking tape and mark it at 1.45" and tape it to the Balancer at 0 degrees.

2.

Bring #1 to TDC and then grab the intercooler fan and rotate the motor to your mark (25 degrees ATDC). This takes a little patience and muscle. You can try bumping it with the starter, but I'm never very successful at that.

3.

Back probe the middle wire of the cam sensor (marked B and normally blue) with a voltmeter. Turn the key ON, but leave the engine OFF.

4.

Loosen the sensor with a distributor wrench or a wobble socket and extension.

5.

Rotate the sensor full CLOCKWISE. The voltmeter should read 7.5+ volts.

6.

Slowly rotate the sensor COUNTER clockwise until the voltage drops.

7.

Secure the sensor at the instant the voltage drops.

The sensor is a hall effect device with a rotating metal ring that is driven from the front of the cam gear via a shaft (like a distributor). This ring passes thru a grooved sensor molded into the sensor cap. The metal ring has a notch or window cut out of it. When the window goes by the sensor, the voltage drops, which tells the ECM where #1 TDC is.

Cam Sensor Adjustment Procedure with an Oscilloscope

1.

Somehow, tap into the ignition module connector. Pick your cam & crank sensor signal & GND from there.

2.

Put 1 channel of the scope on the cam and another channel on the crank signal.

3.

Rising edge to falling edge (and vice versa) on the crank signal is 60 crank degrees.

4.

Falling edge of cam signal occurs 25 deg ATDC of #1 cylinder on compression stroke. Make SURE this is occurring on the compression stroke and not the exhaust stroke of #1. If you do set the cam sensor to the exhaust stroke, it will be 180 cam degrees (360 crank degrees) out of sync - the engine will still run but not as well as fuel will be puddling for 1 crank rev.

5.

Rising edge of crank signal for #1 cyl occurs 10 deg BTDC.

6.

This means that the falling edge of the cam signal should occur 35 degrees after the rising edge of the crank signal. Remember that half a period (rising to falling edge or vice versa) of the crank signal is 60 crank degrees, so use it as a ref to measure the 35 degrees.

7.

Spec is +- 5 degrees so you don't have to be exact. Also, obviously the engine has to be running to do this. Setting the CPS with a scope like this is the most accurate method, although the static method of setting the crank 25 degrees ATDC and twisting the CPS till you're on the borderline where it switches is probably within the 5 degree spec.

8.

The hold down bolt is either a 14mm or 9/16. I always use a 14mm 1/4 inch drive. I've done it with a 3/8 drive and u-joint, but the CPS itself is kinda in the way as the bolt is kinda tucked under it. In some cars (mine for instance), the CPS distributor shaft is put in in such a way that once the CPS is correctly set, the "ears" that bolt the plastic cover to the unit are directly in the way of the hold down bolt so you can't get a socket wrench on it. In those cases you have to pull the shaft out and reposition it.

C3I Module Pinouts

1984-1985

C3I
Pin

Wire
Number

Description

Color

A

423

ECM B4 EST

White

B

424

ECM D5 Bypass

Tan/Black

C

430

ECM B5 Ref. High

Purple/White

D

121

Tach Lead

White

E

951

ECM A11 Cam

White

F

453

ECM B3 Ref. Low

Black/Red

G

918

Crank Sensor B Signal

Green

H

952

Crank Sensor C GND

Black

J

916

Crank Sensor A 12v

White/Red

K

952

Cam Sensor C GND

Black

L

917

Cam Sensor B Signal

Blue LT

M

916

Cam Sensor A 12v

White/Red

N

439

Ignition Power

Pink/Black

P

839

Ignition Power

Pink/Black

1986-1987

C3I
Pin

Wire
Number

Description

Color

A

423

ECM B4 EST

White

B

424

ECM D5 Bypass

Tan/Black

C

430

ECM B5 Ref. High

Purple/White

D

453

ECM B3 Ref. Low

Black/Red

E

121

Tach Lead

White

F

643

Crank Sensor B Signal

Blue/White

G

642

Crank Sensor C GND

Black/Yellow

H

641

Crank Sensor A 10V+

Black/Light Green

J

630

ECM A11 CAM

Black

K

633

Cam Sensor B Sync

Brown/White

L

632

Cam Sensor C GND

Black/Pink

M

639

Ignition Power

Pink/Black

N

631

Cam Sensor A 10V+

Yellow

P

439

Ignition Power

Pink/Black

 

 

Alternative Cam Sensor Adjustment Procedure

Scott Walsh

Cam Sensor Adjustment Procedure

NOTES: This procedure is easier if all sensors are disconnected. There are several sensors in the area and removing the wiring harnesses make your job easier. The intercooler does not have to be removed but removal of it and your serpentine belt will make rotating the engine easier. You must also remove the up pipe and intake hose between the MASS air sensor and the turbo.

1.

Measure on a piece of masking tape and mark it at 1.45". Apply the tape to the left side of the vibration damper at the TDC timing mark.

2.

Rotate engine to TDC, compression stroke.

3.

Install the cam sensor. Cam sensor “window” will face towards the drivers side of the car. You may have to reposition the notch in the oil pump drive to mate with the cam sensor. Remember the gear drive is a helical cut, you will have to rotate the sensor counterclockwise so it will end up in the desired position. (There is not an exact position for the sensor as timing is determined by the adjusting procedure.)

4.

Install cam sensor hold down bolt, but do not tighten.

5.

Re-attach all sensor connections, and replace cam sensor cap.

6.

Turn ignition key to “ON” position. Do not crank engine. Using a voltmeter, probe the “B” wire connection on the harness to the cam sensor.

7.

Rotate the sensor clockwise. The reading on your voltmeter should be approximately 7.5 volts.

8.

Rotate the sensor counterclockwise. As you rotate the sensor, the voltage will drop to “0". Secure the hold down bolt at this location.

9.

Re-connect all sensors

10.

Install serpentine belt, intercooler, up pipe and intake hose.

11.

Ensuring you have checked and topped all fluid levels, go ahead and start the engine.

12.

If you have followed the procedure properly the engine must run.

13.

No further adjustment is necessary, your cam sensor is adjusted properly

 


 

86/87 ECM Car List

Marvin Ballard - marvinballard@bigfoot.com

ECM List

The following is a list of cars that have the same ecm as the '86-87 GN's and T-Types.  They are suppose to be direct replacements less the prom:

I received this list while at the junk yard.  It was generated from there computer using Hollander Number: 590-1554 Electronic Engine Control Module Hollander Listing.

1986

Century

6-231

1989

Firebird

6-231

1986

Olds

6-231

1986-87

Regal

6-231 with turbo

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 



 

1986-1987 Exploded Parts Diagram


 

 

 

 

 

 


 


Wiring Harness Connector Diagrams

Craig Watson
Cal Hartline

Connector C100

Connector C437

 



 

Coil

 

Turbo

 

            Turbo Assembly Bracket

 

     

 

 

 

 

 

 

 

 

 

 

 

NO-START TEST
Below is a series of tests to troubleshoot a 'no-start' condition. (I basically reprinted this from a GM troubleshooting flowchart, hopefully it will be of some help!)

Below are links to repair manual pictures to reference from:

ECM Plug
Sensor Plugs

You'll need to get at the ECM and the cam & crank sensors to do some voltage tests. If you have a NEEDLE type voltmeter, it may work better for these tests, as it will visibly "swing" when the sensor switches open & close (IF they're working okay!)

Here goes:

First, test your meter and ground! (see ECM Plug) Check connection A-6, "ign, ECM fuse" for 12 volts. (for ALL tests, BE SURE the negative lead of the voltmeter is connected to a GOOD GROUND!)

#1- (see ECM Plug) With the key off, disconnect the ECM A-B connector. With the positive lead of the voltmeter, probe the B-5 connection (highlighted yellow, this is the crank sensor signal) Crank the engine and watch the meter...you should have varying voltage from 1 to 7 volts.
If NOT okay, proceed to #2.
If you ARE seeing correct voltage, your cam & crank sensors are okay, and your coil and/or ignition module may be the problem! You need to loosen the coilpack, and check the BLUE wire for 12 volts, key on. If it DOES have 12 volts, then the problem is likely the ignition module.

#2- now probe the A-11 connection... (highlighted green, this is the cam sensor signal). Crank the engine...you should have varying voltage from 1 to 9 volts.
If it IS okay, THE CAM SENSOR IS FINE, AND YOU ONLY NEED TO TEST THE CRANK SENSOR IN ALL FURTHER TESTS!
If it's NOT okay, there's no cam sensor signal!

Plug the ECM connector back in, and head for the sensors!

#3 (see "Sensor Plug") Unplug the cam sensor plug. Turn the key "ON" ...On the MODULE SIDE of the plug, probe the "A" wire for voltage, after which probe the "B" wire for voltage. You should have between 5 and 11 volts on BOTH wires.
If you ARE seeing correct voltage, THEN: with the negative lead of the voltmeter, probe the "C" wire, and with the positive lead probe the "A" wire. You should have between 5 and 11 volts. Note the results, then REPEAT THIS TEST WITH THE CRANK SENSOR PLUG!

If ANY of the sensor plug tests FAILED, you have a probably ignition module problem...
If ALL the sensor plug tests PASSED, then PLUG IN the sensor plugs, and proceed:

#4. Test the cam sensor: Probe the "B" wire of the cam sensor, then crank the engine and watch the meter. You SHOULD have varying voltage between 1/2 and 9 volts. REPEAT THIS TEST WITH THE CRANK SENSOR!

If either sensor fails this test, then it's possible that sensor is bad! If they PASS this test, it's likely the ignition module, or the connections TO the ignition module are bad)

Hope this makes sense!

 

 

 

Single-vacuum hose wastegate

 

 

Dual-vacuum hose Wastegate

 

 

Restrictor

 

 

Riviera