I purchased my G35 sedan last October with I believe almost 38k miles on it. Not it's close to 47k. I've done an oil change and took it to dealer once to fi clicking noice when gear switching (automatic)... About a month ago I started hearing this wierd "rattling" noise. I think it's coming from engine. It "rattles" EVERYTIME I accelrate. I'm not sure if it rattles when I'm on freeway cuz I can't hear. But on the streets: when I accelerate from green light sometimes it's quiet, but then when I'm at around 20mph, and I press gas (floor and not floor) I hear like a bolt or screw or someting rattling under my hood. I'm not sure what it's called, because I have no idea where it's coming from. Can anyone suggest possible issues that could cause the rattle and solutions. Thanks.

 

check on this thread for updates...seems like there's a few of us with this sound. https://g35driver.com/forums/g35-sed...nds-front.html

 

Thanks, I'll look it up

 

Does the rattling sound like small rocks being shaken in a metal can?

 

I can't be specific, but it could be. It's either rocks in metal can or screws, or both lol. The only problem is that I can't tell for sure if it's coming from front or back. (ex. I had clicking noise a while back and I thought it was from engine, but it was from right rear tire). Either way "sloppymax" if you think you've dealt with it before, let me know what happened. Thanks.

 

I have not experienced it in this car but I have been in a friend's before when the engine was pinging. He was using a 87 octane and a cruddy brand at that. If it is only during acceleration then it could be pinging if it sounds like the rocks in a can. Do you typically use the same gas station? Just one of the many possibilities.

 

90% of the time I fill up on Shell and "maybe" sometimes, Mobil. Always put 91. It maks the sound when I accelerate to about 30. Then when I floor past 40 or so, there's no sound

 

Try another brand of gas BP, Marathon or Sunoco and see what happens. You will find these days that so few people buy premium that the tank the fuel is stored in often becomes dirty because it does not get cycled through enough.

 

I have heard that sometimes when a liquid drops down a pipe and hits the curve, it can sound like rocks or metal banging. I hear this all the time in my home whenever the bath tub water is turned on. No leaks or anything like that, just noise.

However, I'm sure there is a solution out there for that, and I would certainly try another gas station for awhile. I did hear where a gas station near me dealt out bad gas (try to hold back your laughter), and the cars that filled up on it would not start. It was a shell station, and I certainly do not go there anymore.

 

Then that doesn't sound like pre-detonation to me.