Review on 🔌 Denso 234-4061 Automotive Oxygen Sensor by Karoly Reddick

I have replaced the upper and lower oxygen sensors. Removing the factory bottom O2 sensor was difficult at 150,000 miles. I did this using a liquid wrench (atomizer), a broken rod, an O2 sensor port and a corolla weight to break it. Just above the rear oxygen sensor, I tape wooden blocks between the exhaust pipe and the bottom of the car to keep the exhaust pipe from moving. With the car on the ground, I use a jack on the end of the switch handle and just keep jacking it up until I hear a metallic pop. Didn't bother with the torch as it's pretty close to the bottom of the car, other things can catch fire. 1 day soaked liquid key didn't work either. I'm sure there are other ways to remove the O2 sensor, but this is how I did it. As for the downstream O2 sensor rubber boot, OEM Denso seemed less reliable than Toyota's original O2 sensor. His instructions recommended wrapping the wiring in duct tape to keep exhaust fumes out. Instead, I used a Permatex® Sensor-Safe High-Temp RTV silicone gasket between the sensor wiring and inside the rubber boot for an airtight seal. The upstream oxygen sensor was much easier to remove (2 x 12mm hex head screws). . Installing both Denso o2 sensors was easy. While no codes and Check Engine do not light up!