Misfire on warm start

[boostngsx]

When I start my car cold it runs fine. I don't have to let it warm up or anything and it drives just fine. When I have driven somewhere come back out to leave 15 minutes later the car starts buck feels like it is missing real bad. I can't even drive it. The only thing I can do to drive it at that point is let it cool down for a while or just drive it until it stops. I don't know if this is relate to my low fuel pressure(19 P.S.I at idle) which has been low for a while. This just started recently. Someone mentioned to me that it might be my ignition control module. Any help would be great. Thanks in advance.

 

[EagleTSIawd]

Knowing that your fuel pressure is almost half of what it should be, I would first tackle that problem. I was running 35psi of fuel (at no vac) and it would make a popping sound from the exhaust every few seconds when idle. I fixed the pressure and the problem went away.

 

[boostngsx]

Knowing that your fuel pressure is almost half of what it should be, I would first tackle that problem. I was running 35psi of fuel (at no vac) and it would make a popping sound from the exhaust every few seconds when idle. I fixed the pressure and the problem went away.

I do agree with that but at the same time I don't. Why would it run fine when started cold?

 

[xe0]

I do agree with that but at the same time I don't. Why would it run fine when started cold?

Just a guess but under cold start the car has more fuel added to the mixture.

Adam

 

[EagleTSIawd]

on a cold motor (when temp sensor sees less than 180F) the ecu will run the motor a lil rich. Once the motor is warm (above 180F) the ecu goes into learn mode and starts adjusting to keep the motor working efficiently or from catastrofic failure. So my theory with your case when the motor is cold, is that the ecu isn't making adjustments to compensate for the low fuel pressure. Although, since it's cold it will run a lil rich which may be what is kepping the motor running. Once it warms up it adjusts to the low fuel that results to your car bucking, dying, and not starting when warm.

That is why I would first fix that problem, it could be that your fuel filter is clogged or your fuel pressure regulator is bad.

 

[Colt4G63 also]

^^^^^^
That stuff is all right, or it could be a bad fuel pump.