I think I may have and I was wondering what your cars acted like when this happened.

Mine randomly runs like crap ( Backfiring surging erratic idle) but when I unplugged the O2 it seemed to do better and steadied out the idle.

 

Did you check the wire yet for any physical damage?

 

yea. I guess putting it like " I think I may have" isn't the way to put it. It melted the harness BAD! It was pinned between the header and the inner fender well on the driver side.

 

Well if the harness is melted that bad, then I'm sure that could explain your array of driveablility problems. By unplugging the O2 sensor, I believe you are forcing the PCM to revert to its set open loop tables which would explain the better idle. Definitely repair the harness and use some cable ties to route it away from the headers.

 

I burned the plug from the computer connecting to the extension, melted together. It's been like this for almost a year, lazyness. If you wait for you engine light to come on the car will run fine, if you don't it will start doing what you were talking about. Mine does the same thing if I don't wait for the engine light, takes about 5 min after startup for it to come on. Shouldn't hurt horsepower really, my numbers are with the burnt wires.

 

I took it for a short drive today ( with O2's plugged in) and right away it started surging and backfiring. It kept dying and eventually stalled and would not fire again until I let it sit for about 10-15 min with the O2 unplugged. And it idled steady at 1400 rpm. Does this sound like a burnt O2 wire also? I just had the motor installed right at 100 miles ago. So I figured there would be a few bugs, I'm just not sure if I've only got one to chase or maybe more.

 

Just get a new connector and splice it in. Pay attention to where the wires go. Only splice one wire at a time. You may have also melted the ground wire that goes to the block also (if its passenger side).

ZMAN

 

I wouldn't ever splice an O2 wire unless it was on an 87 ford ranger! But, that's just me.

 

The connector is melted, so how do you replace it. He is not talking about the wires on the o2 itself, but the electrical connector on the harness. I agree you are not supose to splice the o2 wires to make them extended or if it gets damaged.

So if the wiring harness wire that goes into the connector gets melted or damaged, then how do you fix that? Buy a brand new wiring harness. That makes no sense.

My wiring harness wires that go to the o2's, knock sensor and the ground that goes to the block all got melted together. I spliced in a new o2 connector, and repaired the knock sensor and ground wires. No issues what so ever.

ZMAN

 

OK, if it is the connector thanI wouldn't just toss a splice on there, I would solder it to a new connector. Good job fixing your problem zman!

http://web.camaross.com/forums/showt...ht=wire+solder

Good Luck wlz28

 

When i burned one of the downstream o2 sensor wires on my car it popped the eng. sens. fuse in the fuse block under the hood. might want to give that a quick check.