Gremlin under the hood

[betamatt76]

Alright. I have a 1997 Sunfire 2.4L After the car reaches operating temperature, if you shut it off for a few minutes and try to re-start it, it turns over and will start but then idles extremely rough. Any amount of throttle will kill the car (it sputters and just dies). The car will not run properly again until it has cooled down completely.
The car does NOT over heat...ever. It doesn't even run hotter than it should (according to the dash gauge). Now I have replaced the fuel pump, fuel filter, plugs, crank shaft position sensor, cam shaft position sensor, coolant temp sensor, coolant outflow unit and coolant reservoir cap. The car is not throwing any codes...at all. No check engine light nothing.
I have a friend that is an ASE certified mechanic that has pretty much given up on fixing the problem at this point. Since the engine isn't overheating (either on the dash gauge or from physical inspection), it isn't throwing codes or even displaying a check engine light and we have replaced just about EVERYTHING that could conceivably be causing the problem (yes in weird instances the cam/crank shaft position sensors going bad can cause these symptoms) he has simply washed his hands of the car.
So anyone want to take a whack at this? What's wrong with my car?

 

[melsg5]

have you checked the fuel pressure regulator?

 

[betamatt76]

I don't have any of the symptoms of a bad FPR. So no I haven't checked that. Anyone else got any ideas?

 

[melsg5]

leaky fuel injectors

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[betamatt76]

Nope

 

[melsg5]

is it really that difficult to pull the vacuum line off the FPR to check for gasoline? is it that difficult to pull the spark plugs when it wont start to see if they are soaked in gasoline?

 

[betamatt76]

I don't have any symptoms of a bad FPR. The only symptom I have that is remotely close is hesitation/dying when accelerator is pushed but if it were a bad FPR that should happen on cold starts. Mine happens after the car has reached operating temperature and is shut-off then re-started within a short period of time. I have no mileage issues, no blackened plugs, no smell of fuel in the exhaust or any other bad FPR symptoms. Even the stalling is happening at the "wrong time" to be a FPR. In addition, the FPR was replaced less than a year ago along with the fuel pump and filter.

 

[melsg5]

bad coil pack ground

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[Zimgxp]

Have you cleaned the throttle body and rhe IAC?