hey fellas.. so i bought a 82 trans am. ive been going through it and fixing wiring under the hood. Looks like theres been a lot of hands under the hood doing so called repairs but nothing getting repaired you might say.. So here goes, its just a chevy 350, computer controlled carburetor with i think a turbo 350 transmission. it has a 4 prong transmission wire plug with only 3 wires coming out of it. Only 2 out of the 3 wires are connected to the computer, but the other wire was connected to a green wire that went under the dash but didnt go to anything and didnt look like a factory connection. another minor problem i have is there were a couple vaccum hoses disconnected to the air injection. So... If anyone out there can share a wire harness diagram/ schematic and vaccum diagram that would be sooooo awsome and VERY appreciative. thanks for any help you could offer guys !!

 

TH350 had no computer control so more likely you have a T700 or TH200 with computer controlled lockup convertor

Your 2 wires to the computer ; other one is a power supply wire to a switch on the brake pedal
Power goes through the switch to trans
When you brake , the switch cuts off the power so lockup automatically disengages
to prevent the engine stalling from the convertor being locked up

 

thanks for the reply!! do you have a wire diagram for this ??

 

There should be a switch on your pedal that has power on both terminals when the key is on and loses power off one terminal when the pedal is pushed.
Connect to that terminal
DONE

 

ok great, but wouldnt there be a wire from the firewall balkhead that would be coming from the brake switch from the factory? where would it go? ive seen some wire diagrams and all say it should be ppl.. im guessing it should be purple.. but I found no wires from the firewall bulkhead dangling around and all wires from that bulkhead are being used.. man im really scratching my head over this... lol i really dont want to put a hole in the firewall like an idiot just to hook wires up the right way.. anyone got any ideas where that wire would be??? is ppl purple in a wire diagram?? thanks guys..

 

UPDATE!!!! I still need HELP!!! lol.. so i found a purple or pink colored wire from the ecu that had went to the transmission with the tan/black stripe wire. I tested the pink wire and found it must be coming from the brake switch cause it has power with key on but no power when brakes are applied. but I still have dont know why there is 3 wires coming out from the transmission... Any Ideas guys???

 

How can the wire come from both the ECM and brake switch?
One or the other

If as you say , you have the correct power on pink and the tan/wht control wire to the ECM ;
then TCC should be working correctly
and the 3rd wire would be the 4th gear indicator signal to the ECM

Typical TCC wiring
wire color may vary

 

nice diagram bro!! do you know what vehicle your diagram was for?? here are the schematics i found.. let me know what you think... i have a computer controlled carburetor 5.0l with 700r4

 

the schematic on the right is just a schematic i found on the internet, it wasnt vehicle specific.... my car doesnt have a light brown wire from the transmission or from the pcm.. im thinking maybe i should ground it.. but im not sure...

 

Your diagram on left is identical to mine
Purple ; power in from brake switch
Tan /wht ; control wire to ECM
Like I said ; lockup should be working

NEVER ground any wire unless you know it goes to ground

I would just make the 3rd wire safe for now and see if lockup works correctly