what up guys ... just something i've notice about my g and i don't know if all you guys are having the same problem or not ... so here it goes ...

(i really don't know how to explain it but i'll do my best)

every once in a while, i do step on it ... not redline it but just push her a little hard ... i don't think i've gone pass 6k/6500k but when i do push her a little ... i hear like almost a rattling noise from the engine ... just wondering if i should be concern ... holla back!

 

I think i have a similar problem. Only at low speeds when i get on it there is a weird rattling sound from the engine almost like something might be rubbing inside. But only happens at low speeds. I had the same problem in my last g35. Is this your problem or do you get the noise at all speeds when you accelerate heavy?

 

heavy accelerate only ... low speed seems ok ...

 

Not saying this is the real problem, but two possibilities are pre-ignition caused by too low an octane gas/bad gas or being in too high a gear when accelerating and thus loading the engine down. These symtoms can sound like engine rattle.