Had to replace mine, spent a good bit of time finding OE ones for less than the Lexus cost of $321 each. I found that AutoZone duralast boxed sensors are actually denso for only $150 each. NTK/WVE off rockauto is also denso at least the ones I was sent for my experiment of finding the same as OE parts.

Just putting it out there for anyone who may need this part.

How come you would have to replace them? Never heard of that happening.

They eventually stop working, not as common if you use premium fuel but it doesn't really matter since due to the way they work, that being piezoelectric, once exposed to enough vibration over time they will internally short. The previous owners of my car all used 87 so I'm not surprised the sensors were near gone but I did get 6500 miles out of them and I drive kinda hard. Usually hit redline at least once perdrive since the thing revs nicely

Interesting. Never have I heard of it.