TBI to TPI swap nightmares.... help please!
 

Okay this isnt really for me it's for my cousin. He swapped a 350 into his 89 RS awhile back, but kept the stock TBI unit(it was originally a 305 TBI). Recently he bought a TPI system and the wiring harness.

He got it all on and got everything wired up, but it wont start, the starter wont even turn over. He thought the key module might be bad, but he took his out and put it in my car and it worked in my car. What could it possibly be? He is absolutely stumped about it and so am I.

I am positive some of you guys out there have done TPI swaps to TBI cars with the chips on the keys.

Any and all suggestions are welcome! Thanks in advance!

look in the tech articles here. Not sure if the ECM is different, but I know it will probably need a different prom.

what year is the tpi?

Is the security light lit up?

I swaped an 89 tpi into my 91 and one of the ground wires in the 89 harnes was not in the same place as the 91's and the vats wasn't getting power so it wouldnt enable the starter enable relay.

This sounds like the exact same problem I am having. Where is the ground wire that is different? I am using a 90 harness in my 91.



Thanks,



Jason

with my tbi to tpi swap i had problems with the VATS even though the VATS fuction was removed from the PROM.what i did was i pulled the start enable relay out and i bent the contacts in the relay so it will always stay closed and complete the circuit.it may not be the right way but it works.

AHHH Yea my car was down for the longest time doing the 305tbi to the 350 tpi swap. I never thought someone would be as insane as I! :) It may be a different chip in the key, from your other comp. Make sure the wiring harness is the same year, or your going to have problems. I just got mine done approx. 3 weeks ago. My service engine soon light is on, and i think its going to be on forever. It runs really rich for some reason, i dont know, i've just had so many problems w/ my car in genral i just want to drive it for a little bit. hehe the damn thing went from a 16.5 w/ the 305 to approx. a low 14. I added a mild cam and some headers and what not. It runs like a champ though, good luck.