Knock sensor question

[sy2185]

I noticed the plastic top piece of my knock sensor turns left and right independently of the threads into the block. Is it OK, or did I break it while doing my trans/ motor mounts? The trucks not quite running yet, and still has the trans out giving me great access to the sensor. If it's broken I'd like to replace it while it's still easy to get to.
Jeremy

 

[Loeryder]

Nope this is fine.

The plastic cap at the top is the connector that snaps over the Knock Sensor itself.
It is a single lead down the center and the sensor is grounded through the block.

Good way to test it is hook an AC voltameter to the sensor and tap the block with a hammer.
You should see an AC voltage generated. Forget the range, but it will give you an idea if it is responding at all. Easier yet, hook up a scantool with the Key on but engine not running and tap the black with a hammer, it should register knock.

 

[mrweelr]

Mine does the same thing, I think you're OK. Just hook up DM and tap the motor with a hammer and watch for knock counts.