Knock Sensor part # question

[Paul Clark]

The knock sensor I just took out is 10456287, as is the replacement I bought.
Additional numbers on the old one are 0279-2S.
The new one says 8254-2F.
Are these different parts?
If so, which is correct?
Thanks

 

[mikestertwo]

They are the same. The GM knock sensors are pretty generic. It's the knock module that makes the difference.

The knock sensor I just took out is 10456287, as is the replacement I bought.
Additional numbers on the old one are 0279-2S.
The new one says 8254-2F.
Are these different parts?
If so, which is correct?
Thanks

 

[Paul Clark]

Educate me, for I am ingnorant.
I don't know what a knock module is.
Is there a way to check it?
I'm chasing what I believe to be false knock, and want to eliminate any and all possible causes.
Thanks

 

[mikestertwo]

The knock module is the square black module mounted on the inside of the right fender next to the map sensor labled BLO on the 86's and HKP on the 87's. If your chasing a false knock problem it's most likely not the module of sensor. The way the system works is, the knock sensor is basicaly a microphone that picks up a wide range of frequencies (noises) from the motor and sends them to the knock module. The knock module filters out all the frequencies except those that which it interprets as a knock. If it detects a knock frequency, it sends a signal to the ECM. Depending on the regularity of these knock signals, the ECM will start to pull ignition timing out. The more the severity of the knock, the more timing will be pulled out. False knock is caused by something generating the same frequency noise that a real engine knock would cause. It could be caused by valve train noise, the exhaust hitting the frame somewhere, a really noisey cam sensor, loose balancer, broken flexplate, etc..

Educate me, for I am ingnorant.
I don't know what a knock module is.
Is there a way to check it?
I'm chasing what I believe to be false knock, and want to eliminate any and all possible causes.
Thanks