General Maintenance & Repairs - Starts Then Dies Immediately - Intermittent

I've got the same thread started over in the FI section, since my car is FI.


Dilemma is, just got my new build running and all looks well. Thing is, sometimes (like 3 or 4 times in a row), I'll turn the key over to start it and it will fire right up, but IMMEDIATELY die. I can't give it pedal or anything to try and keep it running. And when I say immediately, I mean immediately. You know how when you start a car and it revs up a little higher than the idle RPM and then comes back down to close to idle RPMs. Well, mine will rev up to the higher and then drop all the way down to 0 instantly.

I've read and read and read and tried several different things, such as changing keys, thinking its the resistor in the key, looked at my tune with HP tuners, made sure it wasn't some weird column lock/vats/other random thing....no luck.

But then, after three or four failed attempts, it'll start the exact same way, and then just stay idling...and I'll go drive it for a while....aggravating..

Any input is greatly appreciated

maybe the fuel pump is starting to go out on it.

Get a fuel gauge and test the fuel pump. I don't think the key/VATS or anything like that is an issue; if it was, the car wouldn't even fire up...

If the fuel pressure checks out.......change the IAC valve. If it acts up it'll open for a start, but then it will close fully and the engine will immediately stall out. And NO, you will not always get a code or SES light when they are failing, only when they completely fail.
But if it starts and drives normally sometimes I would think the fuel pump is fine.

Also, failing Crank Shaft Position sensors will cause your exact symptoms......same thing with no code or SES lights.

If its fuel/spark thats getting cut off randomly it can also be a failing Cam Shaft Position sensor.

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Thx guys.. I've got an AEM fuel pressure gauge on the car (has dual walbro's in the tank) and it's rock solid at 60 psi...even when it dies....the IAC thing sounds like it might be something though. I have a Nick Williams 90, but I'll look into replacing the IAC and trying it out.