O2 sensor + 2000 Jeep Wrangler

#1

I have had 2 sets of O2 sensors replaced by my local mechanics and the Check Engine Light keeps coming on - usually within 25 -3- miles of my spending $$$ to get it fixed. The mechanic said the codes say “Heat monitor did not run” - they give up and I am about to as well - do I junk this thing or anyone have a solution to get it fixed so it will pass inspection - THANKS!

#2

Find a mechanic who knows how to correctly troubleshoot the problem. The code just tells you where to look for the problem, it doesn’t mean that the O2 sensors themselves are bad. It could be as simple as a blown fuse, or as complicated as the engine computer. (Or it could be the wiring.) In any event, with the right procedure it is possible to determine exactly what the problem is, guessing and throwing parts at it are not required.

#3

The exact code would be helpful. I think they are saying that the oxygen sensor heater monitor won’t run to completion. There are diagnostic charts, from alldata.com for one, that your “mechanics” should be following.
The problem is likely that the heater circuits, which includes the oxygen sensors, wiring, power supply, and the engine computer itself, has a problem.
We had a very lengthy post, and a shorter post, on this subject: Your “mechanics” could learn something from these posts; click on this link http://community.cartalk.com/jforum.page?module=search&action=search&clean=1&search_keywords=oxygen+sensor+posts&search_terms=all&search_forum=&sort_by=time&sort_dir=DESC&x=14&y=14 or, you could (hopefully) find mechanics who have already educated themselves and can do the tests and repairs.