can someone tell me if the colors on the passenger front o2 wires are striped or not? heres the deal.

i didn't have a front o2 sensor harness on my car, the rear o2 was the only sensor hooked up on the passenger side. i found four wires coming out of the harness right around the computer and they were cut. i bought a replacement pigtail from efi connections and the colors were exactly the same color. i spliced them together.

i replaced the o2 sensor that was in there with a front o2 sensor and plugged it in, and the car misses and stumbles like crazy. unplug it and its fine. the reason i'm trying to figure this out, is once i got the computer tuned and deleted the rear o2s i've had a problem with idle. when cold it will idle and will stay idling with the ac on, but once it warms up it won't hold an idle with or without the ac on. so i was thinking that i was basically only running on the drivers side o2 sensor. and i have never had a code set for o2 sensors or anything pertaining to the banks running lean or rich. so i'm stumped. and i am getting 75 miles to 10 gallons of gas in the city.

 

Hard to follow the sequence of events. Are you saying that even though you did not have the passenger side O2 sensor connected the engine ran fine, and set no codes? Then you found cut wires up by the PCM, and apparently a missing O2 sensor connector, and when you spliced in the pigtail and connected it to the passenger side O2 sensor, the engine started running poorly and gas mileage dropped to 7.5 MPG?

The passenger side pre-cat O2 sensor wires are:

-solid tan (ground from PCM)
-solid purple (signal to PCM)
-solid brown (+12V from fuse 6 in the under hood box)
-solid black (ground to engine.

No "striped" wires. The tan/white stripe and the purple/white stripe are on the drivers side (Bank 1, left)

 

yeah sorry it was a lil confusing to understand. the only sensor hooked up on the passenger side was the rear o2 because there was no pig tail for the front. and i found some cut wires tucked away under the computer that matched exactly to the color wires on the new pigtail that i bought.

now symptoms before i hooked it up is the car not wanting to idle when it gets warm. so i took out the rear sensor, replaced with a pre cat sensor, and plugged it in where i spliced in that new precat pigtail, and then once it warmed up it ran like crap. i took it to get the codes checked this morning and it came up with stuff about the vss, and fuel pump circuit. if i unplug it, it runs fine no missing. and clear the codes with it unplugged it doesn't set the vss, or fuel pump codes. which fuse is number 6? the cover for my fuse box is not the right one, someone put a cover from a v6. so it doesn't match completely.

 

ok heres the codes that it sets when i hook it up:
p1642
p1641

and its multiple symptoms on both. stuff about the vss, fan relays, fuel pump primary circuit. so i'm guessing those four wires are not for the oxygen sensor. i took the harness apart a lil bit a few mins ago, and the wires that are going to the rear o2 sensor pigtail are marked with a white stripe. and the rear 02 for the driver side i'm guessing, which is sitting on top of the transmission has solid color wires. so my only guess is someone messed up this harness before i got it.

 

Those two codes are for the cooling fan relay circuits. Appears you may have a short in the O2 sensor wiring. In many model years, the cooling fans and the O2 sensor heater circuits are on the same fuse.

Why did you swap a front O2 sensor to the after-cat position? They have different part #'s because they have different heater circuit loads.

 

what i did was those wires i found, i spliced in a front o2 pigtail. took out the rear 02 sensor, and put a front o2 sensor in and plug it in to those wires/pigtail i found. there is a plug on my headers where an o2 went, then down on the ypipe that is where my other o2 is, and they are both before the cat. pluging that o2 into those wires i found also shorted out my vss. last time i tried, thinking i just mismatched wires, it messed up my vss, and i got in the morning and the dang speedo isn't working. so i gotta change that now. so i just unplugged it and put it to the side, and hooked up the rear o2 again which it runs fine, just won't idle when warm or with ac on. and i get crappy gas mileage. i'm trying to locate me another wiring harness and swap that out and see if that helps. i took all the loom off of that part of the harness that goes down the passanger side to the starter,knock sensor,cps, rear o2 and someone has hacked in that thing pretty bad. looks as if it got melted through at one point and time. and they just spliced in there with new wire.

 

basically if i look under my hood, i only have three o2 sensor plugs, the driver front and rear, and the passenger rear. there was no passenger front plug. the only thing i can think of is that plug wouldn't reach to where they had the sensor so they cut it and tucked it under the computer and just put in a rear o2 sensor and hooked it to the rear o2 harness. and my car doesn't throw any codes for oxygen sensors or running rich/lean so thats whats puzzling. i've taken it to two diff places and i've replaced what they told me was the problem, but no worky. maf,tps,iac,iat,temp sensor,coil,plugs wires. and i only have the problems once it warms up, so thats what leads me to think its an o2 problem