Ok so here's the deal, after much deliberation I've decided not to build the motor i was originally planning to build and just go with an LS1 in my 89 bird.

Here's where I'm at, the car will have absolutely no ammenities, no heaters, no a/c, only P/S and Power brakes. I'm running a custom column, interior is cage, racing seats, and aluminum dash with autometer gauges, custom column, and I plan on running a switch panel to control everything (lights, start, etc)

What should I do about a wiring harness for the car? If I custom made one which wires do I still need, where can I find a diagram to custom make one? What have the rest of you done?

 

speartech... great quality , awesome customer service.and no worries. it will be perfect

 

I agree with Patriot68. Speartech did my harness and ECU, the motor fired up and purred on the second revolution. The more I read posts from folks whose cars won't start, the better I feel about having Speartech take care of my electronics. It was not cheap, but it sure was worth it. Plus he has been right on the spot with quick and correct answers to my questions.

Pat

 

Another vote for speartech. I havent finished mine yet but the harness looks great and John Is a great guy to deal with.

 

What about for those of us who don't have the "flow" to go with an aftermarket harness? Is there a forum topic or help section to refer to? Has anyone battled through this and willing to share? That would be great. thanks.... or what price can I expect to pay for an aftermarket deal?

 

The stock one is not that difficult to rework especially if you can read a wiring diagram. I have the 98 f-body harness mapped out, and I reworked a 2001 tahoe harness for my swap, I posted the truck info in the FAQ thread and may have posted the 98 info too if not I can go post it. I do not have a diagram for the 99 harness so I have not mapped it out but I can usually answer questions anyway, the harnesses are pretty similar.

These are some pinouts from another post

99 LS1 PCM to Dash Harness
White (220) Plug
A TAN Oil Pressure
B GRY PCM 32 Clutch Anticipate Switch Signal
C PNK C105-B IGN Power for TCC Stop Lamp Switch
D PPL PCM 33 TCC/Cruse Brake Switch
E BLK/WHT Ground
H ORN/BLK PCM 34 PNP Switch Signal
J YEL/BLK Low Coolant Indicator
K DK GRN/WHT PCM 50 VSS Output

Blue (230) Plug
A GRY PCM 46 5V Feed (Fuel tank pressure)
B Brown w/Stripe PCM 25 MIL Lamp Control
C WHT PCM 45 EVAP Canister Vent Valve Control
E Blue PCM 55 Theft Deterrent Fuel Enable
F DK GRN/WHT PCM 17 A/C Request
G GRY PCM 23 Fuel Ground
H DK GRN PCM 64 Fuel Tank Pressure
J PPL PCM 54 Fuel Level Input
K DK GRN PCM 58 Serial Data (Class 2)



99 LS1 PCM to Front Harness

Large Plug C100 Plug
A PNK Hot in Run and Start (IGN/INJ Bank 1 15A)
B DK GRN/WHT PCM 43 A/C Clutch Relay Control
C DK GRN PCM 18 A/C Clutch Status
D GRY TPS +5v to TCS
E DK BLU TPS signal to TCS
G PNK Hot with IGN 1 Relay Engaged (Tranny/EGR 15A)
H DK BLU PCM 33 Cooling Fan 2 and 3 Relay Control
J DK GRN PCM 42 Cooling Fan 1 Relay Control
K BLK TPS sensor low to TCS

C101 Plug
A YEL/BLK Low Coolant Sensor
B PNK Hot in Run and Start (IGN/INJ Bank 2 15A)
C BRN PCM 36 Air Pump Relay Control
D DK GRN/WHT PCM 9 Fuel Pump Relay Control
E PNK/BLK PCM 19 Ignition Positive Voltage for PCM
G ORN PCM 57 Battery Positive Voltage for PCM
H BLK/WHT Ground
K GRY/BLK PCM 53 TCS Spark Retard Signal to Brake Control Module

C105 Plug
B PNK Hot with IGN 1 Relay Engaged (TCC Stop Lamp Switch/MAF/O2 20A)
D DK GRN PCM 37 Cruise Control Inhibit
F WHT PCM 13 Cruise Engaged Signal
G WHT PCM 10 Tach out to Brake Control Module
H PPL PCM 4 AIR Solenoid Relay Control

These are all of the pins/wires I did not use:
220- E,H,J,K
230- A,C,F,G,H,J
C100- B,C,D,E,K
C101- A,C,K
C105- D,F,H



(thanks to StngKlr for the pinouts)


I attached a post by Mr Dude_1 the connections for a 3rd gen camaro are there.

 

John at Speartech is awesome and I would use him with no hesitation but if you like doing stuff yourself, you want to save some$ and you have a little time it's not that difficult to do your own harness. The added benefit is that you'll understand your electrical system and you'll develop a great appreciation for the genius in the design behind these computer run engines. 1. find out what the VIN of your PCM is. a GM dealer or Delphi parts wherhouse with a TECH 1 or 2 (I can't remember which) can figure it out if you don't allready know. 2. Have your dealer print the pin-out documents for your year and body style. You won't need to do this if you're certain you have the computer that came with your engine. I think it's called the main PCM Connector Ends or something like that. 3. Borrow, or use your imagination (don't buy to keep), the Painless LS1 wiring harness (never mind that it's not for your year or PCM, you're only going to use it for power distribution reference), 4. Order from Painless the appropriate fuse block interlocking pair and fuel pump relay (I may have used the GM fuel pump relay), 5. Use whatever wiring harness you have, get one at a junk yard or off of ebay, 6. Using your pin-out documents run the correct wires from the correct engine plugs to the correct pins on the major PCM, RED and BLUE connecors. Out of the 160 pins, you will use only about 60 of them because of not using post cat O2 sensors, AC, EGR, etc., etc. 7. If you shorten wires for neatness, buy the correct wire end connectors from your dealer and borrow his pliers to crimp them on. Most dealers have a complete Delphi connector kit. A Radioshack crimper (pm me for the #) works well to. I didn't know this when I did mine so to shorten or lenghten wires I soldered them and covered the joint with heat-shrink. Soldering is a snap if you buy rosin soldering paste, tinning stuff in a little can and new solder form Radioshack. pm me if you need any help. I found it very satisfying doing my own and I have the confidence to trouble-shoot any problem.

 

A bump for very good info GMW-CSL

 

I see now why this is the best forum. Thanks for all the information. I do have the right computer for my engine and I have the blue and white connectors that go through the firewall. should i try to get the relay bank from the "doner car" or do i even need it to run the engine? I suppose i need some sort of relay system to run the headlights, and wipers ect. but since my swap is going to a 68 camaro it should be fairly simple. but thanks to G-body and GMW-CSL for all the extra info I feel that I am ready now to take this project on. I guess that it might be more of a headache for you Crazyjim with your gen III car but good luck!

 

I went with the Painless wiring harness through Summit Racing.. must have a 98 computer with service number 16238212 Worked great for me, and affordable

 

Painless harness has wrong pin-out for either '99 or '00 and up but you can use it for those if you change the blue and red connector pin-outs. I would keep all of your chassis wiring intact and continuely check to see that everything works during the engine wiring process, i.e. after you disconnect any wires. Obtain, temporairly, the Painless harness, and use it to copy their fuse block for power distribution.

 

I never had the need to read any wiring diagrams other than just run the correct colored wire from the correct engine connector to the correct pin on the PCM. You do have to have the pin-out documents for your year of engine and PCM or be certain the PCM you have ran the engine you have. The pin-outs are available from your dealer or on this forum, I believe.

 

Do you have any pics of yours we could copy? It's hard to temporarily obtain another harness.

 

What are you wondering about, if its the power dist it looks the same as a 98 harness except for a C105 where pins A and B are reversed. If you have diagrams for a 99 harness I can do a write up like this when I get a chance.

 

Thanks for the write up. I think that will be enough to get it done.

 

Just keep in mind that that is for a 98, the 99+ is different, I checked the pin outs and there is only the one difference in the power distribution, but there are a bunch of other sensor wires that have different placement.

 

Yeah. I looked at the pin outs in the sticky. My motor should get here this week and I will start to mess with it. Thanks for the help. My motor is a '02.

Are there any differences between Camaro and WS6 PCMs?