I HAVE THIS PROBLEM WITH MY GTA RIGHT NOW . FOR THE LAST SIX MONTHS I COULDNT FIGURE OUT WHY I HAVENT BEEN GETTING ANY INJECTOR PULSE. SO I CHECKED AND RECHECKED MY GROUNDS ,THEN I SAW ON ONE OF THE POST THAT IF THERE IS A VATS SYSTEM THEN THAT WILL NOT LET ECM TURN ON THE INJECTORS. I BOUGHT A 1989 GTA CAR NO ENGINE NO TRANNY, NO HARNESS. I THEN PURCHASED A 1987 IROC AND TOOK OUT THE ENGINE TRANNY AND WIRING HARNESS EVERYTHING DOES FUCTION EXCEPT INJECTOR PULSE . THE PREVIOUS OWNER DID SOME CRAPPY WIRING SO THE STARTER DOES CRANK . NOW MY QUESTION IS THE BLUE WIRE THAT IS SUPPOSED TO GO TO B6 AT ECM HOW WOULDGET THIS TO WORK AND CAN I STILL KEEP VATS AND IF NOT HOW WOULD I GO ABOUT GETTING RID OF IT

 

VATS can be disabled in software, buy an Ed Wright chip or other aftermarket piece w/ VATS disabled (or learn to burn chips yourself via the DIY_PROM forum) and it's no longer an issue.

 

i guess my question would can i use vats in car with 1987 ecm w/o vats . doesnt the dark blue from vats send a certain frequency to ecm for ground

 

Not without the VATS decoder box. And of course the key and lock cylinder.

 

the 89 gta that i bought does have the passkey just no engine and tranny,harness the previuos owner had put resister in the plug under dash. he had taken the key part out .I would like to keep vats, is this possible with 87 ecm . my wiring diagram says the 89 dk blue wire from vats goes to b6 at ecm.
VERY STUMPED

 

You have several options. You can get a customer chip with VATS disabled, you can modify the harness (if need be) and use a different ECM/PROM combo that came stock without VATS, your you can simply retrofit VATS into your car.

VATS is a highly effective theft deterrent. Working at a dealership, we see tons of "would be" stolen cars w/ nothing more than steering column damage. Thats why when I retrofitted my '87 to Speed Density, I also retrofitted VATS into the car.

 

I like the idea of keeping it in the car since i have pass key modual and he already has the resister at plug to bypass i do eventually will get the key part in colume
But the problem is b6 on the 87 iroc harness is empty going into the ecm do you know how to wire this in and i know i keep reading about the dark blue from vats that goes to the ecm where does it go ? thanks

 

1987 ECM is same model as 1989 ECM...'165. The PROM/MEMCAL makes the difference. With MEMCAL are you running now...the '87 or the '89?

The '87 wiring harness may likely be missing pins for VATS, you'll need to find a diagram and check.

My '88 GTA diagram shows ckt 963, purple wire, on pin L of connector C207 which is the 2-row hood near the ECM connecting the engine harness that runs thru the pass side fenderwell to the under-dash harness.

Likely you just need to add a purple wire from that location to the VATS box under the dash and you're back in the VATS business. The connector pins are available at your Chevy dealer or Pep Boys (I really hate that place, they discriminate against military servicemen).

 

right now its the 87 . will this make a big differences . everything was pretty much the same except a few wires were different
also purple wire to what in the vats box

 

If you're running an '87 Camamro MEMCAL and PROM, VATS isn't in the equation. If it's wired up right, it should start.

Do you get code 12 flashing on the Check Engine light when the ALDL pins A & B are jumped?

 

code 12 will show . having huge problem with injector pulse thought it mabey could have something to do with th vats. ive rechecked all the grounds getting power to both sides of the injector. i even tried my computer in another trans am and started right up

 

ok does anyone have the more indepth wiring diagram than haynes ,chilton like mitchel or factory manual