What did you do to your NBS GMT800 Tahoe/Yukon Today?

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MassHoe04

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I went to use my map gas--bought a brand new tank--and the brass nozzle was no good. I couldn't get it to stay lit. FML. That should've been my clue right there. I also had my special o2 sockets out. Didn't work either.
Tips on getting old O2 sensors out...

Heat is your friend, if you have a torch. Soaking with a good penetrant, like Kroil, will also help a lot. I used old-fashioned Liquid Wrench and tapped the bung and sensor a little to try breaking the rust bond before I started wrenching...

Since the old sensor is already getting replaced... No fancy O2 sensor sockets required. Cut the wire. Get a good, proper fitting box wrench on there with a piece of pipe on there for leverage. I didn't have a pipe, so I prayed and gave the wrench a few love taps with a 3 lb. mallet. It broke loose. I use an open end wrench to tighten the new one (just the wrench...no pipe leverage/breaker bar) to "good-n-tight" or "tight enough" torque specifications.

New sensors come with anti-seize in the box, to make it easy for the next guy.
 

NoReverseYukon

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I went to use my map gas--bought a brand new tank--and the brass nozzle was no good. I couldn't get it to stay lit. FML. That should've been my clue right there. I also had my special o2 sockets out. Didn't work either.
Those O2 sensors sure don't like you, do they Tony. Maybe a few penetrating oil/drive/cool cycles will help in loosening it up.
 

Tonyrodz

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Tips on getting old O2 sensors out...

Heat is your friend, if you have a torch. Soaking with a good penetrant, like Kroil, will also help a lot. I used old-fashioned Liquid Wrench and tapped the bung and sensor a little to try breaking the rust bond before I started wrenching...

Since the old sensor is already getting replaced... No fancy O2 sensor sockets required. Cut the wire. Get a good, proper fitting box wrench on there with a piece of pipe on there for leverage. I didn't have a pipe, so I prayed and gave the wrench a few love taps with a 3 lb. mallet. It broke loose. I use an open end wrench to tighten the new one (just the wrench...no pipe leverage/breaker bar) to "good-n-tight" or "tight enough" torque specifications.

New sensors come with anti-seize in the box, to make it easy for the next guy.
I tried an air hammer a few times, soaked it a few times too. Trying to get it off with a socket it started to look like the bung(metal)was bending some, so that's where I just left it alone. There's also not a good angle to attack it either. So awkward. BTW--It's in the collector on a long tube header.
 

MassHoe04

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I tried an air hammer a few times, soaked it a few times too. Trying to get it off with a socket it started to look like the bung(metal)was bending some, so that's where I just left it alone. There's also not a good angle to attack it either. So awkward. BTW--It's in the collector on a long tube header.
Understand completely. It is not unusual for even the pros in a shop to cut out the old sensor and weld in new bungs. Maybe it will break free before you get to that extreme... Fingers crossed!
 

mountie

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I tried an air hammer a few times, soaked it a few times too. Trying to get it off with a socket it started to look like the bung(metal)was bending some, so that's where I just left it alone. There's also not a good angle to attack it either. So awkward. BTW--It's in the collector on a long tube header.
Tony....... PATIENTS ..... then take a sit on a stool..... respond to a silly forum post......

Then try again......
 

mountie

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They hate me and the feelings are mutual!
I don't remember what the stuff was, but my brother brought home from a Navy yard machine shop, a spray can of something that really loosened up a stuck bolt/ sensor.

You might try a West Marine store,,, they have some products , auto stores don't sell.
 

Walchit

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Super cheap. Have you heard it running? Can you confirm the mileage? Maybe try to run a carfax with the vin number
I figured it probably has 300k and he's lying to me also. He takes forever to respond and it's hasn't been with a phone number or address yet so I'm not too optimistic. There is another guy with the same combo from a truck with a rusted out frame about an hour from me.

I might try this guys trick to put a red o-ring and maybe a new pump in, but I'm afraid I already drove too far on it. I really just want to know what the problem was at this point.
 

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