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problems with downstream oxygen sensor after thread repair.

1739 Views 8 Replies 2 Participants Last post by  wesyder
Ok so problem started last week i removed downstream sensor on passenger side. The threads on the exhaust were damaged so went i put in new oxygen sensors the threads on the sensor were damaged. I went to a local shop and had a new thread welded on. There are pics included . I drove it 100 miles and i got code p2a04 which is oxygen sensor bank 2 sensor 2 range out of spec. I'm wondering is the brand new sensor defective or did they not weld it properly check the pics. Thanks for the help.
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Im assuming the bung was welded in near the old one, im gonna lean toward the sensor being defective or possibly is the wrong sensor
im working on uploading pics from my computer give me 5 mmin and check the weld its really ugly . funny thing is i replaced the sensor as preventative maintenance because of the high miles on the truck and its been a headache. its a bosch without connector 15730 downstream. Pipe Joint Fuel line Auto part
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Ok... Lol, it doesn't matter if he used chewing gum as long as it doesn't leak, since it was PM can you put the old sensor back or are the threads damaged as well
View attachment 284617 so should i buy a $90 sensor and replace it or go to the shop and have them reweld this? if the sensor is far away from the exhaust because of the new weld being so thick would that throw a code of being out of spec? it looks like the sensor would barely get a reading the way its welded. the ring is thick and i dont know if the sensors should be in more like the original one is?
well i went ahead and replaced the sensor again and reset the car and ill have to wait a week to see if i get a check engine light.

my theory is the mechanic that fixed the thread by welding a new one was that they put the thread ring on there with a few weld then they installed sensor and then turned on truck and check for air leaks then finished welding with sensors installed . possible they could have messed up sensor by welding after installation. what do u guys think
been about 200 miles and no more light. Just bad sensor for future reference.
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