Annual o2 sensor replacement

[kszygc]

Once a year or so I have to replace the downstream O2 sensors on a 99 Silverado. By that I mean the 2 sensors after the converter not the two before. It has the 5.3 w/ auto trans, auto 4x4. The previous owner cut the y-pipe and installed 2.25 inch pipe all the way to the rear without mufflers at all. I bolted on a pair of 4 inch supertrapps at the back end to cut down on my hearing loss, it's bad enough as it is. It has a K&N fitercharger kit and unknown brand of shorty headers. The computer is still stock though. I will get the DTC for low volst and no volts so I pull the sensor and it is in pieces internally. They aren't terribly expensive, I just get tired of replacing them. Anybody have any ideas or experience?

[get me on the road]

Originally Posted by kszygc

Once a year or so I have to replace the downstream O2 sensors on a 99 Silverado. By that I mean the 2 sensors after the converter not the two before. It has the 5.3 w/ auto trans, auto 4x4. The previous owner cut the y-pipe and installed 2.25 inch pipe all the way to the rear without mufflers at all. I bolted on a pair of 4 inch supertrapps at the back end to cut down on my hearing loss, it's bad enough as it is. It has a K&N fitercharger kit and unknown brand of shorty headers. The computer is still stock though. I will get the DTC for low volst and no volts so I pull the sensor and it is in pieces internally. They aren't terribly expensive, I just get tired of replacing them. Anybody have any ideas or experience?

So I'm guessing you have 2 pipes one on each side, from the maniflod to the rear. Correct? If it is then I would put the 2 new downstreams in, and feel how much vibration is around them, if there is alot that could explain the internal pieces being broke. To fix that you could tac a hanger close to each pipe leaveing room to R&R the o2s if they go bad in the future. If possible use those hangers that have rubber straps on them to allow movement.

[G35MIKE]

why not zip tie the o2 sensors somewhere else, and run o2 simulators? That's what I would do.

[kszygc]

I appreciate the replies and information. The additional structural mounting sounds like the way to go. Unfortuanatly, the downstream sensors are used for the OBDII system, and are required for emissions inspections each year. When I have a clearish day, I will crawl under the truck and inspect. Thanks again!

[spudz]

when I had my truck programmed, I had them turn off the rear o2 sensors.. So no matter what, the check engine light will never come on for them. Cost 150 bux to get it programed.

[G35MIKE]

Originally Posted by kszygc

I appreciate the replies and information. The additional structural mounting sounds like the way to go. Unfortuanatly, the downstream sensors are used for the OBDII system, and are required for emissions inspections each year. When I have a clearish day, I will crawl under the truck and inspect. Thanks again!

just wire the o2sim into the ecm, and leave the o2's in as dummies. That's what I did on my car, and passed smog with no problem.