I replaced the head gasket on a 1994 Toyota Camry 4 cyl and now get a Check Engin code 52 which is a Knock Sensor indication. I cannot find the Knock Sensor. Can you explain where it is?

Back of engine just under the intake.

Back of engine just under the intake.

Do I need to take the intake off to see it? I cannot see anything that looks like the knock sensor. I do see something on the front that screws into the block that looks like a sensor but that is right in the open. Can you send a picture?

The one you see in front is the oil pressure switch. The KS is just above the rear engine mount. You will have to have the car on stands and looking up between the engine cradle (frame) and the block. (just above the middle freeze plug)
You could also access through where the tie rod goes through the right side with the wheel off.
Either way is tight because of the engine slant. It most likely just needs plugging in.
Also, I hope you roughted the wire harness away from the EGR pipe. It will melt and cause big problems. Very common mistake in head jobs.
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