Running Extremely Lean

I have a 1996 Chevorlet Cavalier Z-24 and it is running lean. At first I could start it up and it would run good for about 20 mins. but after that it would start to sputter and jerk. So I thought it was the O2 sensors leaning out because I had a bad exhaust leak. I got the exhaust fixed new exhaust all the way header all the way to the muffler. That didn't stop the problem so I replaced the fuel filter and no luck so I replaced the TPS no luck there either. My air/fuel guage is reading lean never touches rich like it is suppose to you know the usually sweaping motion. Any suggestions would be appericated.

Is your air fuel gauge a narrow or wide band?

Narrow bands are only accurate at WOT when the car goes into open loop and just dumps fuel. It would also be a bad connection where you tapped into the O2 sensor wire. If it wasn't soldered in place, it really should be.

Wide band A/f gauges are a true reading, but also run $250+

It's not a wide-band but its not only the gauge the car skips and jerks. It mainly does it when I really get down on it and then when I try to drive normally it starts to skip and the gauge reads lean. Before this the gauge was sweeping back and forth but now it sweeps lean to ideal instead of lean to rich. I checked the connections and there all fine. Do you think it could be the EGR valve?

It could be. EGR's are such a waste on motors. They really don't need them, at least on these cars.

Try getting a used one first before buying a brand new one, they are quite pricey.

Could a plugged injector/fuel system, maybe.

Codes?

Yeah, you probably should have checked the codes before throwing money at it. If you are running lean, you'll get a P0171 code, and probably some others. It might be your MAP sensor. I was runnng rich (P0172), and replaced the MAP sensor, fixed the problem.

Thanks for the information yall. My engine light just went off today so I will check the codes probably tomorrow. Another thing it is after I get down on it and then try to cuirse it starts to spit and sputter I hope its not a burnt valve.

This might help you.

http://www.obd-codes.com/p0171

Ok I got the codes and the only one was for the vehicle speed sensor. So I got it and replaced it and my car is still doing the same thing. I dont know what to do about it. I thought it might be a burnt valve but I talk to a tech and he said it would be sputtering all the time. But what the hell I getting pissed off with it.:banghead: :banghead: :banghead: