Pontiac Repair: 99 Bonneville Fuel Pressure, car parts stores, initial problems

Question
Hi Todd - you successfully helped me before with an ignition issue previously, so I come to you again.

My check engine light will come on if the gas cap is not screwed in properly. It kept happening so I replaced the cap. Now I've had the car die on me while slowing down for stop lights and such. The engine light comes on and it will start up again, but only when I put it in park. I checked the cap each time and it seemed to be on good but there was some gas outside the cap. Is there another component/seal etc that I can check? Since the initial problems, the car now dies more frequently and the check engine light isn't always lit. There also seems to be some chugging and it sounds like its missing a bit - but again, not all the time. I'm now planning my route to work where there is a place to pull over! Thanks in advance.

Answer
Hi Pamela:
well first off the gas cap you got what it from a dealer or an afetrmarket cap? if it's aftermarket get a factory cap. That is not causing the stalling issue but it can cause a check engine light for sure. That said stop by one of the big box car parts stores and have then scan the car for codes and see what code(S) are stored they do it for free. I can't really help you without knowing what code(S) are stored. I can guess but I'd rather know a direction to go in. You could have a fuel pump that just plan and simple is quiting or slowing down cauing the sit and sputter. when was the last time the fuel filter was replaced? a lot of times they are never changed untill a problem like this crops up and the pump dies due to a clogged or restricted filter. so see what is stored and we can go from there. Good luck :)