Knock sensor issue on a B18C

[strider]

I have been seeing activity with the knock sensor. (The engine was tuned on a dyno and the tuner did change the timing from what the base map was.) I wouldn?t have even known about it, but noticed it while running Smanager and doing some datalogs on the S300. It even had it happened on the same tank of fuel as what the car was tuned on, 92 octane, while on the street. But I never hear any knock. This is on an all motor B18C.

Here is what happens.
There is no activity from the knock sensor at any rpm/load until the coolant reaches 177 degrees F.
The lightest amount of throttle can cause it sometimes. I usually see .52 volts to 1.6 volts from the knock sensor.
Heavy throttle also causes it.
I notice it above 3000 rpms.
Earlier on I got a code 23 form the knock sensor, but I think that was due to unplugging / plugging the sensor. (Maybe I simply have a bad sensor.)

This is what I have tried with no change.
93 octane
100 octane unleaded (Mixed with half a tank of 93 octane)
Reducing the timing
Looked for anything loose that could rattle on the block.

The car is sitting until I figure this out. I have thought of disabling the knock sensor, but fear damaging the engine if it is real knock. Then again, having the timing jump around like that isn?t good either. I might also try and re-torque the knock sensor to spec.

BTW, I do have forged pistons if that can play a factor.

Any thoughts why it happens after 177 degrees F coolant temp?

Any way to test the knock sensor with a multimeter?

Any other ideas?

Thanks for the read and any help provided!

[Spunkster]

With the forged pistons, you should disable the knock sensor.

[strider]

I was wondering that...

Thanks again Spukster!