I have a 1999 lumina with 190,000k on it. The problem is that it will start and idle fine but when i go to excell. it will buck and want to stall. Release gas it goes back to idle fine. This only happens on when it is damp or cold. If i run it for a while it will run fine. I changes egr,02 had fuel press checked. I tried unplugging o2 and it run ok for a day then started acting up again. I opened to gas cap and the pressure was great so i tried leaving it loose and so far so good. Any ideas??? I'm stumped!!! Please help.

Thanks,
:headshake :banghead:

Sounds like you need a tune-up (plugs, wires, fuel filter, PCV valve). Avoid Bosch plugs and wires.

Sounds like you need a tune-up (plugs, wires, fuel filter, PCV valve). Avoid Bosch plugs and wires.

I have changed all those and still no luck. Ac plat. plugs. Looks like it might be time for a trip to the dealer:headshake .

Any trouble codes?

Nice to know which engine also.

Nice to know which engine also.
No codes and it is a 3.1 liter. before changing parts and tune-up it had o2 sensor code and egr sensor codes. No codes as of now.

When this occurs you need to check the FP.