Removing an obstinate O2 sensor?

Boomyal

Supreme Mariner
Joined
Aug 16, 2003
Messages
12,072
both PB Blaster and Kroil are solvent based and not intended for anything other than freeing stuck things.

one I bent on the break press at work to fit in on G-ma's old Crown Vic

Yea, I did one on the Mrs's '88 Grand Marquis. I really do not remember where it was located but I ended up having to buy a split deep 7/8" socket to get to it. It was not all that hard to unscrew but the socket was the only thing I could get on it. I still have the socket but that does not help my SIL.

He cannot get a box end or open end wrench or pipe wrench on it and even if he broke the top off the sensor he would still need a deep socket to reach it.

He also has an access problem, even with the car up on ramps. I think he is going to take it to a local Firestone dealer and have them put it on the rack and break the sensor loose.
 
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laurentide

Lieutenant Commander
Joined
Jul 24, 2011
Messages
1,869
That rear O2 sensor can be a real pain in the rear to get out on certain models of car, I know my Jeep was something, it was mounted so close to the convertor that the heat and cool cycle basically welded that sucker in there.


x2 on the Jeep problem. I drilled a hole and welded in a new bung...left the old one where it was, 'cause it wasn't going anywhere after trying every shade tree trick there is.
 

gm280

Supreme Mariner
Joined
Jun 26, 2011
Messages
14,585
If worst comes to worst, you could always remove the section of pipe the O2 sensor is mounted on and deal with it from out under that vehicle. Much easier to work with things in a better shop layout then under any vehicle always.
 

MTboatguy

Fleet Admiral
Joined
Jul 8, 2010
Messages
8,988
Often times, if it cannot be removed, the only options are install a new bung or cut the section out and put a new section in with the new sensor in it, the local Midas shop has to do that quite often in my area due to all of the de-icer used on the roads.
 

ezbtr

Commander
Joined
May 1, 2002
Messages
2,954
oil, let sit a day, torch, wrench that fits and a breaker bar (pipe, etc) over the wrench and some good arm torque, or if you can, apply wrench after before said, and lightly lower to floor forcing tight wrench (worked for me for years on crankshaft bolts :) )
 

Boomyal

Supreme Mariner
Joined
Aug 16, 2003
Messages
12,072
Not being present, I think this downstream sensor was located in the exhaust pipe flange, directly below the catalytic converter. I realized that this was a real hot spot and could make the removal of the sensor difficult. The SIL finally gave up, for lack of skill. clearance and toolage, and took it to a local independent garage.

...but, not before he had soaked it overnight with liquid wrench. They removed it for him and installed his new sensor for $40.

As usual, iboats' forum and all you savvy guys are a great source of experience and knowledge.

The other good news is that the car passed the Texas State Emissions inspection.
 

dolluper

Captain
Joined
Jul 19, 2004
Messages
3,900
Nice to read some'n good.....updates are always what we what to hear thanks Boom
 
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