hey guys. how sensitive is the knock sensor on a 89 iroc with 350 tpi? could a bad power steering pump, alternator, a.c. pump or automatic belt tensioner affect the knock sensor, say if a bearing was making noise or the whole unit was making noise like a power steering pump whine. i am just trying to work out some bugs in my car and i thought this might be causing a problem since the knock sensor listens for ticks and knocks so it can adjust the timing accordingly to give the best performance. i have a whining power steering pump, a noisy belt tensioner and a noisy a.c. pump. thanks.

 

From everything I have read and done, yes, the knock sensor will pick up excessive noise and mess with your timing. Especially the LB9 (305) sensor. We just replaced the 305 knock sensor on a L98 with the transitor trick, and it really smoothed out the timing.

 

If you suspect the accessories are affecting the detonation sensor, temporarily disconnect the belt(s) while you check timing advance/retard with a light. You should be able to safely operate the engine for 3-4 minutes without the water pump running for test purposes.

Personally, unless the steering pump is so bad that the shaft is about to fall out, it shouldn't affect the sensor. The same for the belt tensioner, A/C, and AIR pump.

 

thanks for the info guys. i will try the belt thing to see if there is any difference in the way it runs for a few minutes. i know the belt tensioner could be affecting my engine. i can rev it up a little and you can hear the tensioner rumble quite a bit. the power steering pump whines a little and it also sounds like the bearing is making noise. it does this at idle and when going down the road. my ac pump makes noise only when it is pumping. all of these things are going to get replaced real soon anyway. so i will take of the belt for a few minutes to see what happens. thanks for the replys.