Hey guys... i bought my 2006 G35 6MT about 2 months ago and i have noticed some piston knocking, at the beginning a thought that it was caused by the previous owner using 87 octane fuel but after countless gas treatments and running only 93 since i got it still remains, i did a saefoam treatment and got better but i can still hear it during low rpm acceleration, as you all know pre-ignition is the engines worst enemy and will destroy any engine with time, the knocking causes the rings not to seal properly and oil will be left behind and get burned also it will cause premature wear on piston rings and even a cracked piston is possible , now with this been said... these engines are known for oil consumption, i wonder if this issue has something to do with the problem, i will perform another seafoam treatment to see the results... anyone out there with this problem? if so what did you do to eliminate this issue? let me know and let me hear your opinions...

 

i wonder if the intake spacer 5/16 thermo kit will help? keeping those intake air temps down should, these engines run hot under that limited space engine bay...

 

I think it could likely be down to burning oil, which in turn will lead to reducing the fuel octane rating, i would also presume that its a rev-up model, which where fitted with different ring sets, leading to the oil problem.

However having said that, the ECU should be pulling enough timing to combat this, but i guess its not enough, or the knock sensors are getting tired and not responding with the same sensitivity as new.

If it is indeed knock, then yes your engines time is limited, as it will eventually break the rings and ring lands.

 

Yes its a REV-UP engine, interesting point of view and i think your right... never thought about it like that but makes perfect sense, like you stated...its probably burning oil already and thats what is causing the knock... i will perform my oil change next week and i will drive for 1000 miles and check it again to see where its at.