I replaced mine at 90,000 because the service code for it came up on the check engine light. Since replacing these, I have seen an increase in gas-mileage and thats about all. I believe that there is only one on urs, i could be wrong but get a haynes manual for it and it will tell you. Hope this helps
Last edited by Black96ZJ; 03-07-2003 at 09:48 AM..
There is one just at the exhaust manifold under the hood, and another just after the catalytic converter. One to test before and one after the cat. That way the PCM can detect failed Cat's. I replaced my cat this weekend, but I may change the sensor, because the gas mileage didn't go up enough. I'm hoping to hit 19 to 20 mpg again. I'm currently at 15-17 mpg.
Your '93 has only one O2 sensor, on the front pipe (near the trans pan). It's definitely not a bad idea to change it, since they do wear from the hot/cold cycles and get carboned up. Just a warning, though. Yours isn't fun to replace. The connector is clipped to a harness that runs along the trans dipstick tube. Getting your arm up to it is a real pain in the a$$. You absolutely dont want to try it when it's been running.
boy, you were right. The O2 sensor itself is very easy to replace, it's connecting it up to the wiring harness that's the tough part. I crawled underneath my Jeep to do this job and found that there was no way I could reach up above the transmission to access the plug. It does look like it's accessible from above if I were to remove the center console, and the shifter bezel. Do you know how to do this?
1993 ZJ Limited 5.2 - no mods - Red with Gold (what were they thinking) trim.