I was driving home from work last night and my check engine light came on. I know that it ain't a big deal so I drove on home. Got home and pulled the codes out. I got a 12, 33, and 21.
33 is AC Clutch Relay, which doesn't make sense, 'cause I don't have AC.
21 is O2 Sensor or Circuit. I'm pretty sure that this is the problem. I've noticed that my gas mileage has dropped and sometimes the exhaust smells like it's running rich. Plus, the Jeep's got 77k on it.
Here's the strange thing, I checked my repair manual, and there ain't a code 12. The TJ has a code 12, but the YJ doesn't. I'm clueless.
Any ideas about any of these?
One last note, since I heard the engine running, I didn't pop the hood and see if the engine was still there. Should I have done this? My mom said she thought she heard something running up the driveway.