Review on GM AFS138 Heated Oxygen Sensor - Genuine Parts for Enhanced Performance and Reliability by Simo Whisperer

As my truck has done almost 190,000 miles and I still have four original oxygen sensors I thought it would be a good idea to replace them. My truck has two of these and two of the other item. I've had intermittent error codes on two sensors over the last year and when I checked the live data they were all working. They say that when O2 sensors get too old, they may not fail completely, but respond slowly, fail to meet spec, and send incorrect data to the computer, directly affecting MPG. I used the O2 sensor connector, an inexpensive tool that makes this job a bit easier. It's basically a 22mm (⅞") offset head with a slot on the side allowing it to be pulled over wires. Get it. Three pickups detached from a long breaker and hard push/pull. Once cracked, three unscrewed easily. However, the top passenger-side sensor was frozen solid and wouldn't come loose. I used an acetylene-oxygen torch with a small flame on the soldering tip and heated the connector to a dull red color. Then, while it was hot i slipped on the socket and broke it it was still too tight to turn further so i reheated the plug and it was still very difficult for me to turn another full turn, before I could turn it free.The plug is a threaded ring welded to the exhaust pipe.Try to concentrate the heat on this plug and don't heat the sensor itself.By heating the plug s widens the orifice. I have an 18mm bleeder valve made specifically for the spark plug holes and O2 sensor plug. I ran this faucet through the threads on all four holes. The faucet turned freely in all holes except the one that needed to be heated. These threads were badly corroded and the faucet cleaned them well. I used copper anti-seize on all new threads, but instead of tightening them to 35 ft-lbs as specified, I used an O2 socket and an open-ended ⅞ coupler. Wrench to tighten them by feel. I once removed an O2 sensor connector on another vehicle to the 35ft lb spec, so I'm always very careful when tightening new O2 sensors. I will update this review in a few weeks with any news about improved fuel economy. ---- Addendum: As this is an OEM part I assume it will work and last as long as the original that came with the car. I'll update this review if the sensor doesn't work in any way. This is a very good price compared to over $55 at your local auto parts store. However, I'm deducting a star because the included packet of Copper Anti-Seize Lube is ripped open in the sealed bag with the part. Why not pack the lube separately in a separate bag? The bottom of the grease bag is blown out and sealed inside the sensor bag. Since the box is completely intact, not dented, punctured, or damaged, it is likely some sort of manufacturing defect in the lube package. As you can see from the photos, the sensor is smudged all over and left me with a bit of a mess that needed cleaning up.