Changed plugs, still low Hz knock

IwantMKIII

WVU MAEngineering
Jun 12, 2007
2,477
0
0
Perkasie, PA
Well i tried the plugs, seems they helped quite a bit with just power in itself and lowered my idle about 1K however i'm still experiencing low Hz knock ranging from 0-10Hz. When it occurs my idle is about 950 and on and off i feel a vibration, during which i notice it corresponds with my A/F ratio. Its goes slightly rich where it feels fine, then drops towards lean where i feel the vibration druing its drop then goes back up and repeats. Any ideas?
 

IwantMKIII

WVU MAEngineering
Jun 12, 2007
2,477
0
0
Perkasie, PA
well someone mentioned it could be spark knock...i changed the plugs but still am getting the reading just not as much. Vibration still occurs occasionally as well as mentioned above