hunting idle/stuttering acceleration

A few weaks ago my downstream 02 wiring harness got tangled up in my rear dshaft. It pulled one wire apart, and i but connected it back. Heres the problems my idle hunts, it will take a good 5-10 seconds of steady cranking to get it to start, after that it idles fine for a few minuets then starts hunting bad, iac opens up almost completly, lots of intack noise and it will jump from 250-1200 rpms. I will pull out, and every time after a start up it will stumble, usually right before it goes into the 2krpm for the first time after startup, usually under a load, although it will sometimes do it when i just rev it. Usually i will get tired of it on the trail and unplug the upstream 02 sensor and it does not do this.

this is a 99 jeep, 4 litre auto. It has 117k on the clock, and i have replaced pcm, plugs, wires, rotor button, upstream 02, tb, iac, tps, and the map sensor. I checked for excessive rotor button play, and it seems normal. It will sometimes throw a code when the upstream 02 is plugged in, i think a 132(high voltage) and a 138 (downstream 02 high voltage)..............and of course it throws all the 02 codes when i unplug the front 02. I am wondering why this problem seemed to start shortly after my downstream 02 wires got beat up because this sensor really doesnt do anything with fuel/timing correct? Any suggestions on what to try next?

anyone??? could it be the cps?

Which wire was it that was cut? 2 of the 4 wires for each sensor are for a heater in the sensor. If it was one of those it might have blown the 15A fuse that is under the hood.

hmm, i will check that.....today i started it with both 02's plugged in......the ses light was off.......when it got warmed up i had three codes, 135 and a 138 which are heater circuit malfunctions.

You might have to check each of the wires going to the sensor. Sometimes they will pull apart internally, but on the outside only the insulation is stretched. A good way to test is to grab a couple of feet apart on the wire and give a little pull. If the insulation stretches, it's broke internally, if it feels solid, move down the wire and try again. Odds are, if you broke one wire in the bunch, at least one more may have a problem as well.

It might be advantagious to trace the wire back as much as you can and just replace it with new wires. I would trace it and heatshrink new wire in, that way you eliminate problems that might happen now or in the future with a short or poor connection.

pete