What can cause knocking on deceleration? I just checked my valve lash and I have adjusted all of them in spec. So that rules tappet noise out. I am getting this knocking noise on acceleration and deceleration between 3k rpm to 5k rpm. My PowerFC picks it up as knock and I can also hear it. When I hear it, I immediately release the gas to see if it goes away, but it does not. It occurs mostly in that range of RPM. I have tried reducing my timing between that range by 2 degrees but it still knocks. I did not touch the fuel maps though.

Can someone please help me out?


Modified by garyc17 at 10:08 PM 5/4/2007

 

Anyone?

 

Generally you wouldnt have knock if your throttle plate is shut.

Its possible that theres a mechanic resonance that makes a sound that is dictated as knock. Therefor the knock sensor gives out a false warning.

 

yeah, ur not going ot have knock w/o air.

It must be something mechanical that is doing it.

 

Any leads to what might be causing a sound identical to knock? Will a faulty clutch, flywheel or clutch bearing cause this? I'm still wondering why this sound is only between a certan rpm range. Could be the correct resonace required to trigger this faulty mechanism.

 

how about that crappy ebay muffler popping and crackling on de-accel

seriously though, you sure it isnt your exhaust?

 

The reason I am quite certain it is knock would be my PowerFC handset displaying knock in that deceleration RPM range. Unless my PowerFC is picking up some resonace similar to knock. It does sound like knock from the cabin though.

I am not sure if I should just ignore this, because the knock picked up from the PowerFC is below 60(I am not sure of the scale). The PowerFC manual states that knock above 60 is bad. I am getting 20+ at low RPM and 40+ at higher RPM.

Just want to know what I can do before I hear a loud bang someday.