hey i have a 1991 camaro and i put a ls1 in it, i read that the purple wire coming from the driver side firewall IS the starter wire, i got out my multimeter and confirmed that when put in the start posistion, it shorted with the constant ground... So i hook everything up and my ls1 is ready for its FIRST START UP!! and i turn the ignition on, i hear the fuel pump prime, i turn the key and NOTHING! so im like wtf? i unplug the wire coming from the ls1 wiring harness and touch it to positive and the engine starts right up. bingo Now why doesnt my purple wire work?

side note - after everything was hooked up again i noticed that there is a constant beep when i have the key in the ignition with it set to run... dunno if this means anything. i was just gonna pull the damn speaker

What did you do about VATS?

Have you checked for 12 volts at the chassis purple wire when the switch is in the start position?

VATS is long gone, i tuned it out, along with the other SES lights that bother me, and am running a speed density tune.. there is no question in my wiring harness i made, the only question is why when i checked that the starter wire had 12 volts it seemed to all be fine and now it doesnt work, i didnt probe again though, wanted to ask here first


now VATS on the 1991? i didnt do anything about, im not sure how it works, doesnt it just interface through the ecu? cuz that ecu is long gone.

Hmmm I just thought of something, I am using the original key..... open to suggestions on how to bypass any of this, my next step is to tap directly into the harness for the ignition or to disable the starter relay (if thats how vats disables the starter)

I hit this same snag helping a friend with a '91, it's the car's VATS you're fighting.

The VATS relay is located in the driver side footwell on the left, behind the plastic carpeted kick panel. It has four wires, two big ones and two small ones. Splice the two big ones (hint: one is purple!) and you're in business.

thx dood!!!

he's correct, you'll find the small VATS relay behind the drivers kick panel(or in that area. The two wires you need to splice together will be a purple(the one you found) and a light yellow wire that comes from your ignition switch. Other than that you just need to make sure that if it's an auto trans you're neutral safety switch isn't bad and if it's a clutch, the clutch switch is being jumped or is working right.