First my car has always had a problem myself and my mechanic felt was VATS related but never could figure it out. Whenever I would turn my car off it sometimes would not restart for 3 to 5 minutes. Let it sit that amount of time and it would fire up right away.

Put in 26 lb injectors 2 weeks ago. Prior to the install the car fired up perfect, ran perfect and seemed happy. After the install same, started good, ran good, looked good. Shut it off and it would not restart, at all. Getting spark but no injector pulse. This was with a new custom chip for the 26 lb injectors. So we put the old custom chip for the 22 lb injectors in it and it starts once, runs fine, shut it off and once again, no refire, no injector pulse. Tried the stock chip and a Hypertech, same story. Put in a computer from an 88 S-10 without VATS and it started and ran, not well, but it ran, refired quick and easy every time. Had a new custom chip made that is supposed to have VATS totally eliminated. Car fired up ran fine, shut it off, no refire, no injector pulse. So, we put in a chip out of an 86 Trans Am without VATS and it starts and runs, not well, but good enough to get around.

The custom chip maker, Speed and Performance swears that VATS is totally turned off, but it would seem otherwise since the 86 chip that never had VATS starts and runs the car every time and it doesn't have the old problem of a 3 to 5 minute wait after turning it off for it to refire.

So, what would cause the car to start once then not start again? I'm assuming that with a new chip that VATS isn't initialized or something and after it starts once it initializes and then won't allow a restart. Of course myself and my mechanic have no idea why new fuel injectors would cause this to happen.

Speed and Performance said they changed 5 files to completely turn off VATS in my chip, is that right?

My combo is in my sig.

Any help would be apprecitated!

 

Try jumpering pins "A" & "E" of the starter enable relay and see if that helps. The relay is located behind the left kick panel. The reason your car probably wouldn't start at times might be because the key or contacts in the lock cylinder are worn.

 

Thanks for the tip, we'll try the jumper and see if it works. I don't think the cylinder or key is the problem since the car always starts first try at the hit of the key when it's cold or it's been sitting more than 5 minutes. I also have had 2 new keys made to see if that was the problem and it wasn't. Thanks!

 

Jumpered the A and E pins and it didn't work. What does that do? Any other ideas?

 

Maybe it's not the VATS that is the problem, have you considered that it might be a problem with the way they set the chip up for the injectors. Just a thought!!!!!!!!!!!

 

Even if they did, the car should still run on the stock chip or my hyertech chip, it would just run rich, right?

Also, it is cranking, just won't start, no injector pulse.

I'm really suspecting a problem with the injectors after talking to several people today on the phone.

 

When my VATS f'ed up, it would not turn over. So, if the car is turning over, then I would suspect that thproblem is not VATS.

Tim

 

Starting in 89 they changed VATS so it would only disable the injectors. Prior to that it disabled the starter and the injectors. I appreciate you taking the time to try and help.

 

I have to disagree with you on that 89warbird. Take a look at the circuitry for the VATS and you will see that it goes to the starter enable relay first.

 

Yeah, my IROC is a 1989, so that would tell me that in 89, VATS shuts it all down-trust me, when you turn the key nothing happens.
Tim

 

I have a simular problem, it will fire, but wont pulse the injectors, if you spray something in the throttle it will run from then on. I sent the chip back in and they said it was fine. I have tried everything I can think, new ecm, module, what else would keep it from pulsing the injectors at start

 

Maybe there is a problem with the signal the VATS module is sending to the ECM. Bad wire possibly, or maybe even the VATS module is not sending the 50hz square wave signal to the ECM.

In other words, maybe the VATS module is reading the correct resistance and enabling the start circuit but not sending the correct signal to the ECM.

It's got to know the vehicle was attempting to start or in would not go into the "lock out" mode for 4 minutes, or so.

I'm sure it's disabled in the PROM or you never would get it to fire at all.

I dunno, it's late and I'm wired on tea... so I'm just guessing. Maybe read this; http://home.t-online.de/home/O_Scholz/vats.html

 

Well, still haven't figured it out, Monday 30 lb FMS injectors go in with a new chip to see what happens. If this doesn't work then it's probably going to be time for DFI.

 

The Accel Fuel Injectors were the problem. After installing 30 lb FMS injectors the problem is solved.