Hi all

Could I get some advise on knock sensors, I had replaced these new from
Volvo 5 years ago as a knock sensor kit, that is new wiring harness and
knock sensors. In the last couple of months I have had to clear the
emission light, fault codes logged for front & rear knock sensors,
sometimes twice a month, signal missing or faulty knock sensor.
I only ever use premium unleaded fuel from BP Ultimate or Shell
Optimax.

I have had this occour if I idle the engine to long on start up .ie
hitching up the trailer.

Short running while warming up, which I try to avoid. The light comes
on after starting engine again.

and finally when low on fuel and fuel light is on.

This all varies within the above mentioned but generally the light is
triggered during one of these outcomes.

Thanks for any advise in advance.

Gary.