drew23

I have a 99 that I replaced the upstream 02 today. I had drove it for a few days unhooked with no issues. On the way home this evening it started shifting up and down. Jeep was at approximately 1500-1800 rpm wise and around 50-55 mph when the problem happened. No CEL or other problem indication. I searched around some but, had no luck.
XJ is stock, no lift, with 225 or 235 tires. Any ideas?


Thanks
Drew23

drew23

Anybody, Jeep is a DD and I need help.

VTJeep

first, get it on a code reader. even if there is no CEL, there may be a code stored in there that will give you a direction to go in. then, depending on what that says, id say get new o2's if they are in question. my 99 sport needed a new bank 2 (downstream) but i did both cause there's a good chance the upstream was close behind. dont skimp on quality when replacing sensors like o2's, TPS, IAC, etc. i dropped about 110/ea. for the o2's. and DONT tell me i paid too much~ my budget, my jeep... had one guy say i overpaid, wasnt feelin it. i know that the o2's i have are good quality and i wont have to worry about it again. same for my TPS: bought one offline, autopartswarehouse i think, and it was like 40 bucks, but it was a piece of crap and needed to be replaced... so IMHO, ya get what ya pay for.
anyways, back to the issue, what other diagnostic work has been done to asses your issue? sporadic shifting could be the PCM sending a bad signal. i know theres a couple other things that can cause this.. try doin a search for your issue?