Originally posted by 0psi
After revving the motor up does the idle fall below normal for a second or two? Rod knock would get louder with the more rpm the motor turns. You would know. Your car would start to sound like a lawn mower on steroids.
around 2K rpms or less, my engine makes a kind of shuderring noise. I've popped the hood and revved the engine using the throttle lever, when I rev it to say 5K rpms and let them drop, I've witnessed that the valve cover makes a "nuhnanah" type noise from underneath it. It kinda sounds like a lawnmower on steroids!