Review on 🔌 Denso 234-4061 Automotive Oxygen Sensor by Dan Sturm

Denso 234-4061 is the bottom sensor for my Avalon. It was installed on the exhaust pipe just under the passenger seat and solved my check engine light problem. The electrical connection is located inside under the passenger seat and this part has the exact electrical connection that fits Toyota. Some cheaper ones will require you to cut and splice the wires. The seat is removed with 4 screws. Just tilt it back to get it out of the way. Then you need to remove the floor carpet in the cabin. The only "difficult" part is removing the plastic trim on the hinge side of the passenger door. There is a threaded fastener holding this plate. Unscrew it and remove the plate. The carpet can then be removed so that the electrical connection is easily accessible. I sprayed the old sensor with a PB blaster twice a day for 3 days to get it loose. You can't get slot 02 via this sensor (at least not in my app). You need a large open-end wrench. Not recommended, but I used a small pipe wrench and an extension cord. Often they get so stuck that they simply break out of the exhaust pipe. I got lucky and mine didn't have a thread. If it's really stuck, you can try heating it. If a plug has ripped out of an exhaust pipe, a muffler shop can usually just weld a new one in, so it's not the end of the world if that happens to you.