Alright guys...I've worn myself completely slick on a project that I've been on for the last month.
I've got an 02 GTP in my garage that's been there for the last two months. A little back story here.
A local GM Dealer put too light weigh of an oil in it, probably going to guess it was the new Dexos 0W-30 in it, and it spun a bearing.
We ended up doing a top swap on it, simply because a decent mile L67 is well north of $1500 here. Everything goes great, cammed it, upgraded the valve train, and put SD headers on.
Before the engine went, it was at the same dealer for losing power....They had it a few days, and supposedly did a ton of wire tracing on this thing, gave it back to him, and it hasn't been right since. Now, keep this in mind.
Since we put the SD headers on this car, we had to do the shorter O2 mod for a Corvette to clear the floor pan. After we get everything all buttoned up, we go and take the car out for a test, and things seem just fine. I toss in the tuner to start dialing in everything so that it's all happy, and notice one thing is wrong. The O2 readout is flat....no signal at all. HPT shows it sitting at 457mv, and that's where it stays, all the time. Naturally, I think that the sensor is bad. WRONG. I hook up the stock sensor and it does the same thing. So, what do you do to see if you have 2 bad sensors maybe? You put it on a bench vice, hook up a meter too it, and light it up with a torch...SURPRISE that it's working after a few seconds. I won't really go into detail, but it was cool to learn how to test them out.
So then I go to inspect the wiring because it's not the sensor, and I start peeling back the loom....probably 6-8 wires were completely burned up. Gotta be the harness, right? Well.......Nick finally finds a harness for this thing, it's apparently out of a 2000 GTP, and even though it's far from "perfect" like the guy stated, it'll work. I spent the entire day yesterday in the garage, pulling wire, and cutting and soldering connectors to make sure everything was supposed to be where it was. Fire it up after triple checking everything....and I'm right back to where I was. O2 sensor is still flat.
am I missing here?
The TL;DR version
1 Car had wiring issues
2 Car won't read O2
3 replaced O2 sensor, Replaced Engine Harness, Replaced PCM
4 Car still doesn't read O2, back to square one.
A last note, I have also went as far as to hook the sensor up to my car, key on, and monitor the O2 read out while I heat the same sensor with a torch, and it works. Doing the same thing on this car, won't work.
What are the chances that I've got another crap harness that's keeping this all from working?
Be gentle, I'm not a wiring guru at all.
Originally Posted by Fivefingerdeathpunch
