diagnostic code 21

[conan1977]

Hello and good evening. I have a 92 comanche 4.0. My maintenance light stays on and I have turned the ignition over to get the code. The only code that shows (or if I am reading right) is code 21 (#6 cylinder fuel injection). Anyway, there seems to be nothing wrong with it and I have checked everything else. Is there anyway to get that light off or should I just leave it on. I hate to take it in and have it checked out (costing me an assload). If anyone has any suggestions or is this common. My vehicle has 94k for miles and is very well taken care of. Thanks for your time. Peace and love to all you jeep creeps.

 

Conan

[HOrnbrod]

Code 21 = Oxygen sensor or circuit. O2 sensor or wiring faulty.

 

This is for 91-96 OBDI Jeeps.

[BLHTAZ]

:agree:

Sounds like it's time for a new o2 sensor.

After you replace it, to clear the code you simply disconnect the negative terminal from the battery and leave it off for a few minutes.

 

BTW...welcome to the Club :cheers:

[bigd44889]

yes welcome and ya what he said

[HOrnbrod]

The MAINT REQ light has to be reset by the dealer. It's an ECU timed function in the OBDI models, see below. You either have to ask the dealer reset it, (they may or may not charge you) or pull the bulb, like I did.

 

http://autorepair.about.com/library/faqs/bl134d.htm

[BLHTAZ]

The MAINT REQ light has to be reset by the dealer. It's an ECU timed function in the OBDI models, see below. You either have to ask the dealer reset it, (they may or may not charge you) or pull the bulb, like I did.

 

http://autorepair.about.com/library/faqs/bl134d.htm

oops :oops: I didn't pay attnetion to the fact that he said Maint. Req. light. I was thinking check engine. ;)