Hi, new to the forum, this is my first post. I was hoping to bend some experienced ears on the trouble I've been having with my 4 banger jeep ('93 YJ2.5L)
-My engine will occasionally sputter like it is running rich and I lose power, then it clears up
-My temp gauge or temp sending unit does not work, 90% of the time the gauge needle sits all the way on cold. Every once in a blue moon it will decide to work for a bit, but no correlation to frequency of the sputtering/power loss
-Heat works, coolant level is fine
-Throwing O2 sensor codes: 21 (O2 Sensor/circuit) and 52 (O2 Sensor: Rich condition)
-Sputtering happens both when engine is cold and fully warm (closed and open loop ECU conditions)
-I replaced the fuel filter, didn't clear it up. Fuel pump was replaced only a year ago but unsure of the quality of part used (previous owner)
-Also, possibly related, but maybe not, I think I am burning oil. The oil level keeps dropping and I don't think its leaking. Smells like buring oil when I park. Possibly oil fouling plugs intermittently? Haven't pulled the plugs yet but I have a fresh set I can put in
Could a bad O2 sensor cause the sputtering like that? I thought after it warmed all the way up the O2 sensor would have no effect.. then again if my temp sender is no good my ECU might not know its warm and never go to closed loop.
Could my bad water temp sensor/sending unit or a bad thermostat trick my computer and make it dump a bunch of fuel every once and a while to bog me down like that?
Also I've heard YJ's have a common problem with the crank position sensor.
Stupid sensors! Making my jeep run cruddy! So insensitive.
I appreciate any help/advice/conjectures/wild hypotheses -CHEERS!!