Merry day after Christmas all,

Right - the "check engine light is on". O2 sensor needs to be replaced... I'm assuming there's two - one close to engine and one behind the cat?

Would it be best to replace BOTH of these critters at the same time; don't know previous history of this Jeep... most likely, if I replace one... the OTHER will go bad, right?

As long as I'm under there.... brown dog motor mounts.... are those good to use? Just trying to get this beauty ready for the road..

Thanks for the read,
Mark

 

Any time you post a question here, you should post the model, year and engine. Not all Cherokees are the same. Specific to your question, most XJs have two O2 sensors, but some of them have as many as four sensors and three catalytic converters.

P0135 is the bank 1 sensor 1 heater circuit. While that could be a bad upstream O2 sensor, it could also be a blown fuse, a bad ground or a broken wire. Check your O2 heater circuit fuse before you spend money on the O2 sensor and clean and refresh the O2 circuit ground. O2 wiring issues are a common problem with XJs, so don't be surprised if you do everything you can think of and it throws the code again.

Brown Dog mounts are great if you don't mind a little more vibration. I run the hard rubber BD mounts on mine with the full engine bracket kit. That motor doesn't move from where it's supposed to be. Also, Brown Dog gives a 10% forum discount if you ask for it, so be sure and ask.

 

had same code

 

Thanks guys.... to be on the safe side, I ordered both of the sensors.

Sort of like the old days when I'd do a tune up... I'm in the distributor replacing the points and adjusting... might as well do the condenser while I'm in there.....

-Mark