Pontiac Grand Prix

I have a 99 grand prix gt and it will not stay running, it will turn over and start but after 2 seconds, it cuts off, I have no idea where to start lokng for the cause, It does have gas in it and I was told it could be a sensor, fuel filter or the fuel pump, my relay fuses all look good also. My car has about 140,000 miles on it and I have never had any issues prior, it was involved in an accident but was running fine, I had it sit at a car repair shop for a couple of months and I'm not sure if it is because it has been sitting. Basically when I start it up, it cuts off after 2 seconds
October 8, 2007.

Sounds like a fuel related problem-could be the coolant temperature and oxygen sensors giving the computer a wrong signal instead of increasing fuel its decreasing it

Have the fuel pressure check and comeback with the readings with and without the pressure regulator.

Oct 10, 2007.