Pontiac Repair: 96 Firebird 3.8 all stock, purge valve, emissions systems

Question
The car runs and idles fine. Doesn't leak any fluids, temp is good oil pressure is fine etc. I drive it everyday. I just bought it 3 months ago, so I don't know any history on it. It has one problem and one code. Which the two don't quite fit together. The code is P0441 and the problem is when I press the gas the car bucks, dogs down and basically runs like crap. Like it has no power, just kind of putts along, so I just keep the pressure on the pedal and it will start running fine again. It is very random. Does it when it cold and when it's warm, sometimes it doesn't do it all day. Also on occassion when it acts up it backfires thru the breather, at least that's where it sounds like it's coming from. I know absolutely nothing about cars and I had it to the garage and they gave me a whole list of "possiblities" for the code. My wallet doesn't allow for me to play parts roulette for very long. A few parts I can afford but not a garages' guessing game. So they replaced both purge valves...one they had to drop the tank for and the other was under the hood that's all I know. I still get only the P0441 code and it still has the problem. Please help...

Answer
Hi Jessica:

well the purge code doesn't make a lot of sence with the issue you have going on herfe to me either unless you have a problem with the evap canister where the charcole is breaking apart and getting sucked into the purge valve on the engine. Unless that valve was stuck wide open it shouldn't effect the way it runs that dramatically. I think you may have another issue here. thetre is also a purge switch I belive on that year car it's in the vacuum line right near the purge valve I have seen them stick on and cause the light to light and that could be thne issue here. 1995-1996 are trickey years they had a lot of new gardgets for the emissions systems and depending on when it was built and what state it was sold in determined wether it had that switch or not. 1996 was the first year for OBDII which was a differrnt emissions dignostic system and to put it bluntly that years sucks for trying to find issues. As for the backfire I hightly doubt that the 441 will cause that. I woulkd look at possibly a bad ignition coil or wire to a spark plug especially if this happens more often in cool and damp weather. the plug bwires would corrode on the tops of the coilds and cause all kinds of misfire/backfire events. so that is where i nwould start looking.. besides that I would look ayt fuel pressure and volume when was the fuel filter last changed? air filter? Use OBNLY AC Delco spark plugs nothing else no magic splitfires or double platinum XXXX brand just genuine Delco plugs and if it needs wires Delco wires as well or a name brand wire kit like Bosch or Echlin from NAPA. good luck :)