Knock Sensor Installation

Hi guys,

Is there a specific tightening torque limit for the common Bosch aftermarket knock sensors?

If it is to be mounted together with another bracket on the block, is it expected to have any influence of the bracket eigenfrequencies?

Thanks

There's almost certainly going to be a torque spec for the knock sensors in a factory workshop manual, however it's really not something I worry about too much. You're usually going to be using an M8 bolt so you can't put too much torque into these bolts without stripping threads in the block or breaking the bolt. I aim for a moderate level of tightness that most people who regularly work on their cars tend to develop by feel over time. If you're worried then by all means seek out the torque value from the workshop manual.

To answer the second part of your question, no, a bracket won't affect the knock frequency as far as I've seen.

Thanks. The sensor is the Bosch sold by haltech and there was nothing mentioned in the documentation which came with it. This an extra sensor, since none was originally installed on the car.

This "torque by feel" would be my target, I just wanted a second opinion, in case the sensors are particularly sensitive in torque, which would affect the bracket held with the same screw.

Your reply clarifies everything. Thanks

Unsure if helpful but...

http://www.ngkntk.com.br/automotivo/en/produtos/sensor-de-detonacao/

"The knock sensors have a specific torque. The torque change can affect the signal generated by the sensor. NTK recommends torque of 2.0 to 2.5 kgf.m and does not recommend the use of grease or washers on mounting the knock sensor."

For sure helpful! Thanks