2000 Impala intermittent stalling at startup problem

I have a 2000 Impala and it has a 3.8 V6 and in the past year intermittently when i start up it will stall. I will repeat and it will refuse to stay started. I can keep it running using the gas and brake making sure to keep the gas on to keep the car running. what i have noticed is when you gun the car it sounds like its missing a cylinder and has no power. Now this happens mostly after i get off work. I will drive it on the highway and keep both feet on the gas/brake… the car runs and 95% of the time after getting home its fine… doesn’t stall and runs fine right after. This drives me crazy as i have taken it to a dealer and they cant get the car to do this for them!!! Then I will get in the car in the morning and the car is fine… runs great… this happens at least once every 2-3 months… Like today, i had the same thing happen and this time on the way home i noticed the car stalled as it was running… i was like this isnt good on a curve and quickly got it running again… this only happened once before. normally after its warmed up it runs fine till the next time it acts up. I have been told it could be a wiring problem or a fuel pump going out… Well how would a fuel pump fix its self?? and work for 2 months to act up again? i had a Mustang and when the fuel pump went out, you couldn’t even get it to start. any help is appreciated!!

I have a 2000 Grand Prix GT. Is yours throwing any codes(check engine light)? I had similar problems last year and no codes. The car would stall out at red lights and when I tried to start it, it would sound like it was flooded. Eventually it would start. Shop couldn’t find the exact problem. Sometimes I would go out and try to start it and it wouldn’t start either. The last straw was when my wife was driving home and it stalled and she was able to turn into our development and coast downhill to our home. I researched the problem and it seemed it could be crankshaft sensor, camshaft sensor, fuel pump, or ignition module. My shop doubted it was fuel pump or ignition module, so I told them to try replacing crankshaft sensor (even though they recommended waiting as they didn’t want to throw parts at the car). That seemed to fix the problem. No stalling since spring of '08.

Yes, there is a nice long list of things it could be. Start cheapest: swap/ change the fuel pump relay; and, the fuel filter. Results?

You might also have the EGR valve checked for leakage.