Pontiac Repair: motor problems, pontiac firebird formula, vacuum leaks

Question
1989 Pontiac firebird formula 5.0.   My car is lacking power and when I'M driving on the freeway, it jumps,hesitates,jerks. My check engine soon light keeps coming on. When I read my code, it tells me that my oxygen sensor is lean!? How do I fix it not to be lean? And how do I make it run smooth again? It is fuel injected. It also pings when accelerating. Ive giving it a tune-up,replaced my TPS, timed it, and much more.Im a single mom,doing my best. Please help!

Answer
Ok there are a couple of things that could be causing the problem. If the engine is running lean its either because the oxygen sensor is bad and its telling the computer that it is seeing a lean condition when it really isn't lean. Or you do really have a lean running problem, usually caused by a plugged fuel filter, vacuum leaks, or low fuel pressure. If I were you I would take it into the dealer and have it properly diagnosed so that you know exactly what is wrong instead of replacing any more parts. It will cost you alot less to have the problem diagnosed and repaired, than it will to keep trying parts.