displacedtexan

So got a check engine light that required me to replace the front passenger o2 sensor... I did, now I am getting a P0138 which is the downstream one.

I was able to get the front one off with an offset o2 sensor socket and a bit of PB Blaster.

Having trouble getting the downstream one off.

Any tips?

I am still using the offset 02 sensor socket with a 3in extension from the front right wheel well and no luck.

Should I try a straight o2 sensor socket?

Also read about people using breaker bars to loosen them up. How the hell do you guys get them in there?

Also don't want to round it off any more than I allready have...

Thanks!

Jason

rob_engineer

I'm not much help, but I do know there are different quality levels of O2 sockets. I had one with a wide slot. This allowed the socket actually flex open a bit due to the high torque, which rounded out the nut. I went out and bought another socket that had a much narrower slot.
Have you tried after allowing the engine to run to heat the sensor up?

OverKill

Same thing happened to me. Took it to an exhaust shop, they welded in a new bung and put the new O2 in it, no more problems. They charged me $30. They kept the old one in to plug the hole. They put the new bung on the side, sour is easier to get to.

displacedtexan

Thanks for the tip. Bottom line, I had to do a very similar thing.

Took it to a custom exhaust shop, they cut out a four inch section of pipe and welded in a new pipe with new bung.

Cost me $125 in Hawaii, they probably spent a few hours on it.

How would the dealer deal with the problem?

Replace the whole exhaust? Crazy...

Rednroll

I had trouble getting mine off using an O2 sensor socket as well. I cut the wires and put a 16in length closed end wrench on it which provided a better grip than the O2 socket and enough leverage, where it came right off after messing around with it for an hour with the O2 sensor socket, impact wrench, PB blaster, heating it etc. It seemed to finally be the right tool for the job.

OverKill

Not the whole exhaust, just new cats. It all one piece for both sides, they are $250 at rock auto. A pain to replace. There was a thread a while back about replacing them. Where do you wheel in Hawaii? You on Oahu?