Update: I took my MAF out and cleaned it with some special non-electrically-conductive cleaner. I figured I would get some use out of my filter-charger kit and clean and reoil my K&N. It was dirty as hell, but after cleaning both of those and getting it rescanned all I have left is the P0420 (Drivers, pre-cat O2) code.

I'm hopefully going to run up to autozone today and see if they have the slotted socket I need to get the O2 sensor off. It looks like it's going to be a bitch to get at (especially without that piece).

Do ya'll have any suggestions how to get it off?

 

Best way to get it off is to 1st spray it down with WD-40, or some kind of lube, and let it sit for 20 mins.

Then use an O2 socket + rachet and a big wrench on the rachet handle for leverage. You could also try a 7/8 wrench directly on the O2 sensor.

BTW: www.GMPartsDirect.com is where I ended up getting my front O2s from; a lot cheaper than Autozone!

The part number for the front O2 is:

ACDelco p/n#: AFS75
or
GM p/n#: 25312184

Thomas.

 

Wow! That thing is stuck on there. I didn't think it would be this much trouble to get the damn thing off. I soaked it with some PB catalyst and let it sit for 20 minutes. It didn't do the job All my bigger (longer) wrenches have too large of a head to fit up in there, so I'm stuck using smaller ones. (it's not gonna happen with adapters either).

Bah...I guess I'll get out there and try again.

 

You're changing the driver's side front O2, right? Mine was pretty easy to get at from underneath the car. It will be on there pretty tight, but a little leverage should break it free.

Good luck,
Thomas.

 

After another spray of PB catalyst and letting it sit on there I tried again. This time with a different socket and a larger wrench -- with the larger wrench it was much easier. I had the leverage I needed to twist it off. I'm not sure if I should go ahead and take off the passenger side and clean it while I'm at it. It looks pretty difficult to access from above. Thanks for the reply

 

Ya, O2s can be a pain, as they go through so many heat cycles. Glad you got it off ... hope it clears up your codes.

It would be a good idea to replace the passenger's side pre-cat O2 the same time you replace the driver's side one. It's always a good idea to replace them together, but not necessary. If you're just going to clean it though, I wouldn't bother.

Thomas.

 

what would you clean o2 sensors with ???

 

I dropped (just the sensor | head) into a coffee cup of carb/choke cleaner. It got some of the deposits off, but didn't seem to fix anything. After replacing the O2...it didn't seem to fix anything -- both sensors codes came back on. I bought a new PCV valve and I'm changing that tomorrow.

 

where is the pcv valvle on the lt1's ??? How can I check it , I have a high idle problem and I cant find where the extra air is coming from. IAC counts drop to 0 at idle.