Jeep Wrangler Forum banner

04 Engine wiring harness

906 views 3 replies 3 participants last post by  wildrnesxperienc 
#1 ·
I think I have screwed up my oxygen sensor wiring. I used contact cleaner on the connectors, which I shouldn't have done, and on top of that it was the wrong kind of cleaner. Had a lubricant in it and I think its affected the resistance of the o2 wiring harness. It caused two lean codes to come up, the jeep idled really rough and stuttered at 2K rpm. I have since cleaned the contacts with CRC a couple times and gotten another round of all new NTK sensors. The CEL is long gone and it runs normal, except a more rough idle than before I cleaned the contacts the first time, a stumbling feeling at idle. And sometimes the idle dips down to the first dot, I'm guessing that's 350K rpm or so? I have changed the TPS, IAC, MAP, and have a coolant temp sensor on the way. There are no vacuum leaks per my mechanic and the throttle body is clean, along with the IAC housing. At this point I am afraid I damaged the wiring harness. I emailed a couple junkyards to see if I can locate a used 2004 engine wiring harness today- Daveys Jeeps, Simpson Family and JW Jeeps. Anyone have one laying around? Or even just the oxygen sensor part? I would just splice some connectors in, but I've read that shouldn't be done as it can negatively effect the resistance and therefore the info the computer gets. Any help would be much appreciated!
 
#2 ·
Sure are throwing a lot of parts at it in what appears to be a random pattern

Lots of money and inducing so many variables ( including the possibility of poorly functioning new parts) that you will have a hard time sorting it out

Check harness resistance with a meter
There is no point in randomly replacing stuff
 
#3 ·
I'm in Statesboro GA, there is a jeep salvage yard here in town. I'll be heading out that way tomorrow. If you like I can check on that wiring harness for you. But you shouldn't need the entire harness. At best you just need the plug assembly to the sensor with enough wire to splice into the harness
 
#4 ·
The rough idle happens 90% of the time. It's rough enough to rattle things in the dash and doors and its driving me crazy. The new parts didn't change it at all. I'm just trying to replace easy things that could give a rough idle like that. The rpms flutter a bit too, like a bit of a misfire. The flutter was there before all this but it didn't run so dang rough. The jeep only has 64,000 miles on it, it shouldn't be doing this.

Sure DP40, if you see a 2004 with what appears to be a good harness could you give me a call? I'll pm you my number. I have read you shouldn't splice into the O2 wiring harness because you could introduce more resistance, so I was thinking either replace the whole harness or just pull out the whole O2 harness in a used harness.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top