1991 Explorer Check Engine Light

[da_tibmeister]

I have a 1991 Ford Explorer 4x4, and the check engine light only comes on after driving in-town for a while. After immdeiatly restarting the vehicle, it goes off. The other symptoms are that the engine is running rich, detirmined by gas smell from the exhaust, and high or rough idling. I'm thinking it's the O2 sensor, but the guys at Autozone told me that unless the CE light stays on, they can't pull the codes. Now, I'm thinking that this beast is no different than most other cars with ODB in that any troublecodes are stored until cleared, and that the CE light comes on only at the time of the fault. If this sucker had an ODBII system, I would just by that nifty CarChip and let the darn thing log away, but I can't
So, any advice would be wonderful.

Tibmeister

[wiredone]

In my 91 I've had the code's checked and didn't have any problem. I'd try going back at a diffrent time and try to catch some else working. Or try going to another store if available. If it is running rich though I'd try to clean the maf 1st and see if it changes anything. It's free so it can't hurt. If you're not sure how just do a search and you should find instructions on this. Good luck

[camper21]

I was told by a shop that the "check engine" light would come on occasionally on 91-92 models because the factory gasket material used on the oil pans would break down, fall into the oil pan clogging the oil pick-up screen and cause a low oil pressure reading. This might be true?