Tried everything to get it out. I did succeed in rounding it off. Am going to have to take the header off and get after it on the work bench.
I'm so pi%$ed. SC

 

Did you give it a good bath in WD-40 first? I actually twisted a manifold bolt off because I didn't use that stuff. I gave all the other bolts a good spraydown and let that soak in a few minutes before I tried losening the bolts. The rust is probably your whole problem. I would also suggest using a torch or something to heat the header around the sensor before trying to take it out. So the sensor is cool and small, while the header has expanded.
That stuff should help for when you are finally able to get a hold of that sensor in there to get it out.

What methods did you try already? I would always like to know of other ways it can be done.

Ty

 

Try heating it with a torch first, if that doesn't work, I don't think WD 40 will do it either. By the way, isn't WD 40 flammable? Don't heat up the manifold if you just added WD 40.

 

wd-40 is key! never arive in the garage w/o it. before i wnet to get everyhitng out i doused the entire exaust with it and it punched through 14 years of rust like nothin'

 

iof its rounded off, a good adjustible spanner wrench gets a nice grip.

 

i actually foudn stuff that is better than wd-40. it is called pb breaks loose. this stuff is awesome. not very many stores carry it, but is worth looking for.

later
tim

 

that pb breakloose does work very well i picked up a can at advanced auto. looks generic but works well...when i took my manifold off it was easy half my bolts were barely tight. i figured it would be a fight but it wasnt. was pretty tough to get that o2 sensor out for the first time since i had the car tho.

 

Any penetrating oil should help, but be careful if heating it because they are flammable. And please make sure to use plenty of anti-seize on your oxygen sensor this time.

 

I left it in.
After I cleared the ecm, I never got another O2 code.
Checked my fuel pressure, and it was way high - 17psi at idle! I'm blaming it on a partially blocked fuel filter that I replaced at the same time as my new intake install. Thus the super rich condition. I reset my vAFPR to 9psi idle/15psi at WOT. Runs real good now. I don't have to deal with that O2 sensor for awhile
SC

 

PB Breaker will take rust off the titanic.