jer4251

iTrader: (6)

ok, so we swapped a 90 iroc tpi engine into my buddys 88 tbi Camaro.

used the
90 engine harness
90 engine
90 ecm
90 gas tank and lines
90 transmission.

both automatic cars.

engine is in and connected up, but we have a mismatch between the 90 engine harness and the 88 interior harness.

ive read going from 90 tbi to 90 tpi requires 2 wires changed. but going back to an 88 wil require repining the harness to get it to function. but I cant find the exact info needed to do so.

can somebody please assist? been waiting months to get this done and over with.

jer4251

iTrader: (6)

been reading over all the info I need. seems the c100 bulkhead is fine for whats being transmitted through it as is. cant find anything I need to move.

c207 plug on the other hand just has the speedo wiring difference between the years. from what it looks like.

speed sensor enters the c207 plug from the engine side, and there is no wire on the receiving side of the plug, so that's where I need to add a wire to get the signal to where it needs to go.

which leads me to my next question. does that wire go to the speedo, and back to the ecm? or to the ecm...

aliceempire

iTrader: (14)

Bottom of the page has c100 and c207 diagrams....http://www.austinthirdgen.org/?pid=19


TBI uses a speed buffer box for the speedometer. You'll need to bypass that and go straight to the speedometer from the ecm. Not too difficult, I did it on my 92, just needed the diagrams.

jer4251

iTrader: (6)

spent most of the day working on the car, and reading up on both wiring harnesses, c207 plug and c100 plug.

from what ive gathered today, I need to move 2 pins on the c100 bulkhead.

move the wire going to G4 to the E6 position, that's the fuel control

also, move the wire going to G8 to the F8 position, this is the alt, fans and starter.


as far ad the c207 plug, everything entering from the engine bay to the pass footwell matches up to the correct ECM, since I used the set from the same car. the only problem will be the speedo, not a big deal right now.


Is that correct?

aliceempire

iTrader: (14)

It's been a long time since I've done it but that sounds right.

Dyno Don

iTrader: (7)

The '88 is a cable drive speedo ...right?

If so the yellow/purple wires on the engine side of c207 are not used. They went to(B9/B10) on the ECM with a MAG VSS sensor.

The TBI has an optical sensor on the back of the speedo the wire from that goes to the c6 connection on the new ECM. However you will need to change it in the PROM to "optical". (not MAG)

HTH

aliceempire

iTrader: (14)

Good catch! I totally blanked about it being a Camaro. I tend to forget the Camaro's were still cable driven when the Firebirds went electronic, even though my older car IS a Camaro.

jer4251

iTrader: (6)

I have the 730 ecm. And the 730 harness. So my main wiring is correct. I don't need to repin the entire ecm clips. Just the (2) c100 bulkhead wires I listed above. And then just getting the speedo right.