Fuel Knock?

[WHOSNXT]

I was wondering what this is and what it means like is it dangerous to drive or what. This guy I know says thats what this knocking noise is I mostly hear it when im idling. And is it dangerous to drive it with the chip I installed about a week ago? It comes and goes its not doing it all the time, I first noticed it right after I changed the oil then a day or two later I put the chip in. Any help would be appreciated Thanks Travis

[WHOSNXT]

Nobody ever heard of this? I just no what he said is there such a thing? And if so does anybody know what to do about it?

[Hawker]

if it comes and goes it could be something else, possibly a bad injector. although, you'd hear a bad injector while you were driving too.