Header installation - front O2 sensor won't budge

[JD Cross]

I have a very corroded O2 sensor in my front exhaust manifold that I can't budge. The O2 wrench I have is spreading open a bit under heavy load so it's not useful. My 22 mm wrench and hammer blows is not effective either.

Has anyone found a way to remove the front heat shield with the O2 sensor still in the manifold?

If there is a way then I can get at the manifold nuts, remove the manifold and deal with the O2 sensor when it's out of the car.

All help appreciated

Jim

 

[OneRedNSX]

Have you tried heating up the area around the o2 so it expands a bit and then try to get it to break free? I usually do that or just soak it in penetrating spray for a while...

 

[JD Cross]

Have you tried heating up the area around the o2 so it expands a bit and then try to get it to break free? I usually do that or just soak it in penetrating spray for a while...

I don't think we're supposed to use penetrating oil on the O2 sensor but I've pounded on it so much I think I'll have to replace it anyway.

I'll go for the PB Blaster spray first.

A little reluctant to get a torch into that enclosed area if I can avoid it but if the PB doesn't work then its heat.

Thanks
Jim

 

[OneRedNSX]

I assume this is on the stock header you are replacing??? If so why not just take it off and work on it out in the open?

And no, you don't want to douse the o2 in oil. Just enough to work its way through a few threads to loosen things up.

 

[JD Cross]

I assume this is on the stock header you are replacing??? If so why not just take it off and work on it out in the open?

And no, you don't want to douse the o2 in oil. Just enough to work its way through a few threads to loosen things up.

Before you can remove the front manifold you need to remove the heat shields to access the manifold nuts.
The only way I can see to remove the heat shield on the front manifold is to remove the O2 sensor.
Have you figured out a workaround on this?

Jim

 

[Larry Bastanza]

Jim,

If you are really stuck, you can manipulate the shield to get it off,("manipulate" interesting word). Also if you have to, snap the back portion of the 02 sensor off, remove the shield, then remove the manifold. A 22mm impact socket/gun will remove the sensor easily, once the manifold is on the bench. Been there, done that. Sometimes they are just a bitch.

Regards,
LarryB

 

[JD Cross]

Jim,

If you are really stuck, you can manipulate the shield to get it off,("manipulate" interesting word). Also if you have to, snap the back portion of the 02 sensor off, remove the shield, then remove the manifold. A 22mm impact socket/gun will remove the sensor easily, once the manifold is on the bench. Been there, done that. Sometimes they are just a bitch.

Regards,
LarryB

I've taken off the upper O2 wire clip, and the black backer board, but still can't quite "squeeze" the shield off.
I'll break the sensor off and deal with it on the bench as you suggest and order shiny new sensors for the shiny new headers.

Thanks for the help Larry

Jim

 

[EdinKali]

One last thing you might want to try is putting a hose clamp around the O2 sensor wrench to keep it from spreading(this may or may not work depending on which wrench or socket you have).