Went out to my weekly start up on my GTA and no start. Turn the ignition switch and fired right off then died...Cranked and cranked it after that with no start. I let it sit for 30 minutes, then tried again. Same thing. Fired off on the first try, then dies. Tried this several times during the day. Fires off on first try, then engine turns over and over and over. I hear the fuel pump run when I turn the ignition switch to on. I also swapped out the ignition module with a spare I had, but got the same results. Any member have any ideas on where to start troubleshooting ?

 

did you check oil pressure ... iirc, the pressure must build to keep the fuel pump on ... could also be the coil is shorting inside, getting hot fast and expanding, causing it to fail, then it cools and starts ... if it were me, i would see if the pressure builds, if it does, i would try to hit it with some starting fluid once it dies and wont restart, just to see if it is a fuel problem and go from there

 

if it wont fire on starting fluid, pull a plug, ground it, and see if it is firing ... if not, i would check the coil

 

Oil pressure ? I would have never thought that. I did not pay attention to my gauges while trying to start my car, but I'll check today. Will do the coil check today.

Thanks Barlow

 

Vats? Ignition control module?

I ls swapped my gta and we had the same exact issue. The car would start and run for all of one second then die out. As soon as we turned vats off in the tune, it was alive.

 

Also ohm all the injectors, I had the same problem with an '89.
One of them was shorted.

They should all be 15 ohms or higher.
I found one @10 ohms, I just put another injector on that wire and it started right up. (7 cyl. of course)

 

Hate to ask but, is their gas in it???sounds like a fuel problem.

 

No problem....Yes...Have gas...Pushed the needle valve in on the Schrader valve and gas came out....Been doing some research on-line and came across that it could possibly be a VATS issue as CashMunson mentioned. I guess the circuit will shut off the current to the injectors after 3-4 seconds. Can anyone confirm this ? So if it is a VATS issue, what are my options ? I don't want to go and butcher up the wiring. Has anyone have luck with a by-pass module ? Then I ask myself, do I really need the VATS ? What advantages do I have keeping the VATS other than keeping it stock ? I can find a stock VATS module off feebay, but don't I have to have the same Ohm reading ignition key ? How does one find out ? I can find out what Ohms my key is, but don't know much about the module. I believe it's located behind the driver's side kick panel. Is this correct ?

Thanks everyone....

 

I would just do the bypass and see if that fixes the problem. If that does fix it then you can simply fix whatever issue there is with the vats system, and you'll be back to normal. If that doesn't do anything, then you can continue to look elsewhere.

 

you can have vats tuned out of your chip, no hacking required

 

The best thing to do is to isolate what you are missing: fuel, spark, or both?

Spray throttle body cleaner (VERY LITTLE) in the intake. Does it run and shut off? If so, you have no fuel but you have spark.

If it doesn't fire, you don't have spark. This doesn't necessarily mean that you have fuel though.

A quick way to determine whether or not your VATS is causing a problem is to scan the vehicle for DTCs.