The knock sensor is in the engine V under the intake manifolds and coolant crossover pipe. As it requires considerable disassembly and an expensive new gasket set to reach it, I suggest you make sure that there is something wrong with it first.
You will have to remove the upper and lower intake manifolds and coolant crossover pipe assembly to reach it.
Keep in mind that, just because you are receiving a trouble code for it, does not mean there is anything wrong with it. This sensor shares a circuit with other components that often will set a "ghost" trouble code.
In the engine compartment
1999 - 2002.
The CKP sensor is located on the left side of the engine compartment on the transaxle housing.
the elictronic control sinsor at on a 93 mercury villager
The cam sensor on a 1996 Mercury Villager cost about $35 to $40. The sensor is actually manufactured by a Nissan subsidiary.
There's no need to replace knock sensors, and there was never a 3.6 engine.
The crankshaft position sensor is at the rear of the engine where it joins with the transmission bellhousing. It is at the left (front) side, not far from the starter.
It is the intake air temperature sensor , and it,s located in the air intake boot.
The knock sensor is under the intake manifold, which has to be removed. This should be left to an experienced mechanic.
Screwed into the lower intake manifold right at the center of the engine in front.
It is under the intake manifold. Darn hard to get to and expensive to change.
the sensor on the 3.3l mucury villager is integrated into the distributor