Weilun Sun

if it possible VVEL system? but sound very similar knock....
oh god....

Weilun Sun

hey guys
yesterday i went to the local shop
him use iSCAN-II(On-Board Diagnostics 2) adjust my ignition timing
the noise was disappear so far
so i think it might knock sound..
i'll keeping watch

Nxf0

Thanks for the update! keep us posted.
if you don't mind me asking, how expensive is adjusting the ignition timing?

Weilun Sun

for free
I just went there for maintenance and he just plug in general obd2 to diagnosis if any error or not
-----------------
11/15
the noise still there but rarely appear maybe once or twice
i think i'll change my redline 5w30 to mobil 5w30 see what happen

antirice

iTrader: (2)

I really doubt the noise comes from inside the engine. I don't think anyone has been able to reproduce the noise when revving the car in park.

Nxf0

oh I got my hopes up and was planning to visit my mechanic this weekend and see if he can plug in obd2 to diagnosis. lets see if oil change helps.

Nxf0

well , I notice this sound today. I am not so sure how and if this is related to original issue being discussed in this thread "Infiniti G37 noise when accelerating after stop "

but here is the video of my car from today. notice the rattle noise while car in park.
it seems like it is triggered by vibration at a certain frequency.

Weilun Sun

when u parking u can pressing the brake + accelerator paddle both about 1600~2000rpm u can hear that noise

guy from norcal

iTrader: (2)

Mine just started making that noise too. To me it sounds like engine pinging. Only does it when i accelerate slow. I was gonna try some octane boost next fill up. I just switched my oil from mobil 1 to pennzoil ultra. Not sure if that has anything to do with it.

Victory

that's a different noise. Probably your catalytic converter

Victory

One thing we are pretty sure of is that it's not pinging. If it were it would be reproducable under other situations

guy from norcal

iTrader: (2)

Perhaps. Of course the g37 doesn't do anything when you want it to. A very stubborn car.

Weilun Sun

can't believe that ...no one solve this problem
there is more case from G25 then G37 in china website...some people say its piston ring....
concluding all possibility it may be 1.ignition timing 2.VVEL system 3.oil? 4.....

Victory

As we've mentioned, ignition timing is unlikely as it doesnt occur under load. VVEL isn't even active at the RPM range we are talking about, nor does it exist on the g25. Oil is not an issue. Essentially we have a bunch of cars whose only similarity is that they make this noise and no one has ever found anything broken.

After an hour tapping under the car with a plastic mallet, the only thing i could get to resonate is the large metal heat shield between the exhaust and the driveshaft

Weilun Sun

so after u solve that noies?