Like many, I have an off-idle hesitation problem when the engine is warmed up... but it's perfect when cold. After testing and/or replacing many suspect components, I'm down to the O2 sensors.

I seem to recall reading that these are tough to remove due to the heat cycling and corrosion in the exhaust system. If true, any recommended strategies for replacing them? I'd normally just soak them in Liquid Wrench but I don't want to do anything that would foul the new ones.

Thanks.

 

I just did mine and they weren't that hard to get at once I rented a o2 removal set from Advanced auto. It was offset, kinda like a crows foot wrench. I would have never gotten a wrench or socket on if I didnt rent the tool. This was on shorty style headers btw.

 

I've heard that they're fairly easy to get off if you heat them up first with a torch. Just keep the flame near the O2 bung so that the threads can expand a little and go to town.

I have the cutout O2 sensor socket and they're easy as heck to get off using that, as long as you can keep the socket steady.

As far as I know, using liquid wrench on those would also work, but I doubt that it would work as well as the torch method.

 

but to make it easer for removal you should just cut the old wires so you can get a deep well socket of it. be sure to use a 6 point also..if you dont have a torch then soak with pb/freeall/liquid wrench overnight.. apply it several times.. just dont mix the 2 (freeall and fire).. lol

 

OK, seems like a blow torch is the way to go then... that, plus the correct socket...

 

2 months later... still haven't done the job yet...

a further question... when I order the new sensors, are the wires/connectors included or do I need to order those separately?

 

The wires and connectors are included with the sensors. I'd buy AC Delco replacements only; aftermarket sensors have a bad reputation.

 

x2 - AC delco parts

A torch helped getting both mine and my buddies out of our stock manifolds. These things were in so tight PB blaster wasnt able to do much but it still doesnt hurt. Make sure whatever tool you use is strong and not a sloppy fit - you can expect this to need some shock treatment with a hammer.

 

Don't forget the anti-seize when re installing.

 

can you get Delco's at any parts store or is this a special order thing? what's a good price for them?

 

the new ones should come with anti-sieze already one them. some parts stores have ac delco most sell bosch.

 

If you are trying to save the sensors, do not use penetrating oil on them. The oil can get into and block the passage that allows air into the inside of the sensor thimble.

Do not load them up with anti-sieze. The AC/Delcos come with the proper amount of conductive anti-sieze on them.

Usually, running the engine will heat the bungs up enough to make the sensors come out easier.

 

If the threads are damaged upon removal then you can get a spark plug thread chaser (can't remember size, but it's the larger of the two standard sizes). The threads are the same size/pitch.

 

18mm x 1.5

 

I just put some Denso's in my 94 T/A and they made a big difference. I knew they were old, but the passenger side one was a real PITA!!!! HTH


tia

andy schuck