any input here would be much appreciated. i've done some searching and can't find any real answers to this. once or twice a year, i get a knocking noise coming from somewhere in my engine bay. i think it's coming from the passenger side somewhere. the sound comes up really badly at the start, it sounds like a hollow knock, like if you were to knock the engine with your knuckles. it goes in time with the revs and sounds absolutely terrible. thing is that if you take it for a bit of a drive . . . taking it easy on the revs and change gear really early, it seems to stay under control . . . to a point. then is gets better and maybe the next day or the day after it's gone all together.

this has happened once or twice a year since i got the car 5 years ago. it's a r33 gts s1. the first time it happend it was after i'd parked on a bit of a hill overnight, but the last few times that hasn't been the case. the last time i'd been mucking around around in the fusebox and hadn't started the car for only about a day. there doesn't seem to be any common factors that cause the noise.

any ideas?

that would be the little asian man that nissan put in your engine to make the car so good.. i think yours might be a little worn out and doesnt wanna be there no more.. take it to nissan for a replacement