on my '98 5 speed, The engine has a rough idle, and under load, usually trying to accellerate in 3rd gear and on up, i it will start missing until rpms hit around 2.5k or so. The engine did throw up some O2 sensor codes saying it was showing lean. I checked the sensors they seem to be ok. Can anyone give me any ideas? possibly a vaccuum leak? i wouldnt THINK it would be plugs or plugwires. because when i replaced them all at the same time it was still doing it, and i haven gotten any misfire codes. Any help would be appreciated.