So, I also have a knock sensor related question.

My 1996 4Runner started displaying a check engine light indicating an issue with the knock sensor on back 1.

I took everything off of the engine and pulled and tested the knock sensors.

Both sensors show an open circuit between the terminal pin and the sensor chassis. (good)

When I plug a volt meter into them, one sensor shows about 2 mill-volts and the other shows about 6 mill-volts. In both cases, this voltage increases when I strike the sensor with a wrench. (good)

It looks like I have 2 good sensors, so I checked the wiring harness. It showed only a few Ohms of resistance from one end to the other. (good)

As it turns out, the replacement wiring harness I purchased on Amazon came with _2_ knock sensors!

So, (finally?) here's my questions:

What should I do?

1. Put the original OEM sensors back in and simply replace the harness?
2. Put in the new, non-OEM sensors in with a new harnes?

Given that I also found a heater hose that had sprung a leak under the intake plenum and filled the cavity with rusty coolant, could that explain why I got the CEL even though everything seems to test out as good?

What else should I check in order to clear the CEL?

What else should I consider replacing while I'm this deep into this engine?

Am I missing anything?

Thanks in advance,

Mike.