[bigblockpaulie]

Hi, I have tried and can't quite get the socket on the top rear sensor. Any tricks?? (96 Deville) Can you tip the motor any?

And the after cat sensor is rusted in. Even with an impact gun it won't budge... I du no.
Thanks

 

[Ranger]

Remove the torque struts (dog bones) and replace the longer one with a small turnbuckle. That will allow you to rock the engine forward an inch or two.

 

[ewill3rd]

Sometimes if a socket won't work I sneak a regular 7/8" wrench in there and try to get it out.
If the O2s are frozen in the pipes you are looking at replacing whatever they screw into. If they won't come out, forcing them is not going to leave you with a hole that a new one will go into.

I often price out the pipes on older cars because I see this type of thing a lot, when selling O2 sensors that is. I know it's not a fun prospect.
Sometimes using two combination wrenches will break stuff loose but it's likely your O2s are "frozen" in.

 

[ocjmakaveli]

ALL U NEED is a 22 mm wrench most of the time and a blow torch thats it.

you heat it up for 1 minute and then turn it will be easy

i've done over 10 sensor replacements and I've never need more than a 22 mm wrench gloves blow torch and a hammer to hit the wrench in case it wont budge.

 

[Eldyfig]

Like OCJ said, heat the area up or start the car and let the exhaust warm up. It will make it easier. Trying to remove it cold will probably damage threads.

 

[ewill3rd]

Yes, using heat might help... but it's no guarantee.
I agree it's definitely worth a try.
Just be prepared if it doesn't work.

 

[bigblockpaulie]

Wow all good help, thanks. I did try the torch on the pipe around the sensor and the impact but no go. I can get a solid bite on it with the box end but can't get enough leverage with that shield welded in front of it. I'll try again getting the car higher. I'll do the bones trick too for the front one thanks; see I knew you guys have heard or had done most stuff on this forum before. thanks! but in case this sensor never comes out what cat-backs work that open it up some.

 

[bigblockpaulie]

They both came out!!! I did the bone trick and it worked, and the after cat I tightened it a little to break it loose with a box end and a hammer then sprayed it with PBlaster penetrant and worked it back and forth not forcing the threads and badda-bing.

 

[Eldyfig]

badda-bing badda-boom, there you go.

I like PBlaster. Stuff is great. Like the smell also.