Pontiac Repair: Engine problem, auto parts stores, catalitic converter

Question
I have a 1999 Grand Prix Supercharged 3.8 liter 6 cylinder....recently my car has been having problems...its slow to accelerate...my check engine soon is lighted...i have already changed spark plugs...but its no that...and when its cold outside and its been sitting out there it has trouble starting and when it does start it idles!!!when i would floor the car it would take off fast but now i floor it and it just like takes in air or something but it doesn't go as fast!!!

Answer
Hi Junior:

It souls like either you have a fule delivery issue of the engine is not breathing properly. You could have a plugged fuel filter, A restricted air intake suppy to the engine like somethging may have gotten sucked into the air cleaner/air filter or lastly the catalitic converter in the exhaust is restricted. If you goto one of the "big box" auto parts stores the will scan the car for codes for free and at least give you an idea as to what the code(s) are for. Good luck :)