hey
i have a 06 g35 coupe and yest i opened the hood and had my buddy hit the gas and it sounded like the engine was knocking but then i did it this morning and its sounds normal and then i let it warm up and drove it around for a little and it still sounded fine. Any ideas on why it would be knocking once and then not again.

 

well i don't know for sure, but if it really was knocking, i'm sure the check engine light would come on.