erratic idle

[donkeyhigh]

Well here is a new one for me. My 92 Festiva automatic check engine light comes on when I first start it, but goes off after about 7-10 min. Then when warm, when I stop at a light, sometimes the car wants to launch, as if it has revved up a little. Nothing consistent, and sometimes it stumbles a little when slowing down. Might it be an O2 sensor? Thanks, I checked the archives but no luck.

[mechanicaldj]

i hope you have a haynes repair manual.

i would check the mass airflow sensor and the throttle position sensor

then i would make sure that the idle air control motor is clean and the throttle plate itself is also clean.