What does spark knock sound like?

[Ruger_556]

I hear everyone talk about it and have no idea what it sounds like...

 

[98_k1500]

Its a chattering sound when the engine is under load. I can make my vortec do it if you pull it below 500 rpm at wot. Almost a rocker arm chattering sound.

 

[BoxerPitMix]

x2. I had it from time to time at low RPM under load until I did a tune up.

Here's a video where you can hear it pretty descent
https://www.youtube.com/watch?v=ttFy48SViTI

 

[twomanymontes]

It sounds like marbles in the motor when you accelerate. Detonation is a bad thing! it's basically igniting the fuel too early and fighting against the piston travel.