Is it really not needed? I can't seem to find the engine side of the wire harness to reconnect my O2 sensor to it. I think it's somewhere in the mess of wiring under my intake manifold.

 

You do need it and you most likely want it too. I can't really help you find the wire in your ''mess.''

 

Is it NEEDED? Well I have been driving with a broken one for the past week (installing a new one today) with no apparent affects. If I didn't have a A/F gauge I would never have known it was broken.

 

The stock ECU with run a bit rich under cruising ranges.&nbsp You'll notice a significant drop in mileage...


-Ted

 

hmm I wish I could find it after reassembly of the engine it just wasn't there anymore. Anyone know where the wire comes from or where it's originates. Maybe I can trace it down without tearing everything apart again

 

The o2 sensor isn't needed. Is it better to have it sure because you get much much better gas mileage, but i drove without one for about a month and saw no negative side effect besides the gas.

 

Oops, duplicate

 

You can see it on the passenger side exhaust manifold. IIRC, it leads somewhere close to the rear of the manifold. Without it, the car runs rich and can cause damage to the cat, etc. It's good preventive maintenance, IMHO :-)


'87/GXL 2+2
207,858 Mi/Engine Mods=0

 

I can see and get to the o2 sensor just fine off the header, I just can't find where the other end is that it connects to. I've seen the area that it's in on my buddy's FC but that wire isn't hanging down there probably because the way I installed all the wiring.

Guess I just need to know which wire loom it come out of to try and track it down

 

so if I have straight exhaust with no cats do I really need the o2 sensor? I just want to avoid taking the manifold, tb, and everything off again to get to the wireing

 

If you don't have cats, I'd think it isn't needed, but am not positive. Hope someone else will chime in, sorry.

 

you can follow it all the way back to the ecu and splice it in there.

 

I'd have to find it first...don't know what the wire looks like. If I could find it I'd just hook it up

 

What car model, year you have ? Didn't see it in the profile.

hugues -

 

86 sport
just put in a ported engine with an s4 block, s5 rotors, and TII housings

 

look, just run a wire from the o2 sensor through the firewall in the pass. side of the car. pull up the carpet and look at the ecu. patch the wire into slot D2. that will be the second largest connector. Its the second wire from the right on the bottom row.


G E C A
H F D B

the wires run in alphebetical order if you pull out the harness and look at it from the connector side. I didnt pull it out and instead just reverse the alphabet like i show above.