Hey guys i currently did a tpi swap in my 88 firebird formula that had a 305 tbi 5 speed t-5 in it, I took the tpi's ecm, ecm to engine harness, and complete tpi engine, and hooked the tpi engine up to the t-5 that was in the firebird, my questions are the wiper motor on the firebird hooks into the c100 pin that the engine stuff is on and the camaro's wiper motor hooks up to the lights portion of the c100 pin what would i have to do there to get the wiper motor to work with the 91's harness and what wires do i have to switch around on the c207 connector to get everything like gauges to work?, is the 91 tpi sd?, and with what i have done, do i have to bypass a vss?, also i noticed on the auto tranny i have two connectors, i am assuming one is for the speedo and the other im not sure, and there is also two on the t-5, and on the auto harness the conection pieces are different...any suggestions would help me out greatly...thanks

 

So the camaro tpi eng. harness is from a 91 auto. car right?
Yes a 91 is speed density,and all 90-92 f bodys had the wiper motor through the headlight harness side.
Please let me give you a little advice.
(get wiring harness from a 90-92 firebird complete from bulkhead conn. to t/l harn.) I've already been down this road,also I hope you already know that camaro and firebird tpi eng. harnesses are diff.

 

The two connectors on the auto tranny are TCC/4th gear sensor & VSS.

The two connectors on the T5 are back-up switch and, should also be VSS (I'll gladly accept correction on this).

 

thanx for the info, is it possible to wire up the camaro harness to work with the 88, my friend is really good at wiring and also has access to mitchel?

 

Shouldn't be a big deal.

 

i also read on here that alot of people took old tpi's and put them in the newer 3rd gen, where as i put newer into older if i got a sd vss from a t5 90-92 camaro/firebird and then bypass the vss buffer in the 88 in theroy my speedo should work?...where as the vss in the 88 t5 was not sd

 

Do you have diagrams for 88 for C100 and C207? All I can find are 87 and 89...
Also did you manage to get everything woriking? I am doing the same thing (91 TPI into 88 car) and the wiring is what Im fighting right now..

From what I saw C100 needs repining of the wipers and brake warning switch..

On the C100 88' there are two connections for fuel control E6 (red wire) and G4 (tan/white wire) - on the C100 91' there is only one, also G4 but the wire is grey.. I dont know if conecting those two would be ok?

There is a matter of G8 from 91 which is a wire that goes to the fan relay and in 88 car it is in a C207 (pin D) connector.. I assume conecting the wire from C207 to on in a C100 connector would be ok..? On the other side, the 91 harness pin D is TPS.. I dont know what to do with it...

Also pin M on the C207 88 conenctor seams like the same thing that is C7 on the C100 conenctor - conencting those two wires would be ok?

 

yes i got everything except the altinator repine couldnt figure out where it was so i rewired it to the battery with a toggle switch, the wipers were tricky i eneded up repining the wires right into the c100 boot connector and didn't bother with the camaro's it wouldn't work, i will try to find the diagrams for you they helped me out alot...any other questions let me know...also you are going to need the vat system out of the donor car or you will not be able to start the car, i suggest getting a vats delete chip off the ebay and puting a aftermarket alarm system on the car.

 

I did what i wrote before - everything is working fine. Also I am burning my own chips so VATS was no problem.
There is only one thing I need to do.

I need to get my speedometer working.

Firebird 88 underdash wiring from V6 with buffer box
with
Camaro 91 engine wiring harness 730 computer.

From what I know ECM sends a signal through grey wire B11 (also in an IP connector) to the speedometer..
And I need to connect that grey wire to.. something.. :-)

I tried to connect it to the brown wire that goes from a buffer box (which is also in an IP harness but and in diagrams it is called "TBI only" ) but it didnt work. Any ideas?

 

you have to wire your tack wire to one of the wires coming from the the computer that goes to the vss sensor in my case i think it was the grey wire from tack and brown wire to computer from the vss, not sure if the v6 wiring is the same, all i did is found the wire coming off the computer that went to the vss and tried every wire until i got the speedo to work, but i will take a better look tonight and get back to you.

 

The grey is true, I knew that.
I tried connecting the grey one with the brown wire from the buffer box (it is also the brown one that is in IP harness) and it did not work.
Please check if you can :-)

 

I would like to bring this thread back to life because i am putting an 88 tpi in my 90 camaro and repinning the C100 the 88 has two connections for fuel control E6 and G4 so is putting both together alright?

 

I connected G4 with G4 and left E6 unconnected.
But I had 91 engine iwth older car, you have the other way.
From what I know E6 i for 9th injector so I belive you could get one new wire from the 9th injector to E6, doesnt have to be throug C100. Or you could use custom PROM and disable the injector.

EDIT: Actually you should see on the diagrams if the E6 goes directly to injector and then do it I do not have diagrams for pre-90 engines so cant check..

 

injector already disabled, after you left it disconnected though did you car run alright? and maybe you can help me out the E6 wire goes to a 5 wire plug near the C100. What is this plug heres 2 pics of it

 

Like i said - I was doing newer engine to the old body so it is 100% different then what you are doing. I had everything right except I didnt get the speedo to work.. before my engine blew up :P But that was not due to wiring, just a bit too much power for not forget bottom

I see no such connector on my diagrams but like I said 0 I only have them for 90+ engines..
From what I see there are a bunch of oranges which are just 12V..

 

well thank you anyway, something tells me something should be plugged into that plug i just have no idea what

 

i am installing a 1990 5.7 tpi in a 1953 pick up with a stock harness how do i hook up the fuel pump, i only have the engine harness from the firewall out

 

Ok, speaking of VSS buffer boxes. Here's one for ya. I have a 91 Firebird 350 tpi with a 7730 ecm. The car was originally a tbi car. I am still using the tbi 700r4 and i still have a buffer box behind the panel in the dash. The car has normal TC functioning too. How is that? Only thing is my speedo won't work. My vss buffer box is the yellow one and looks to be hooked up like it should. I tried jumping the two brown wires together on it pins c and f i think?