Re-posting it in proper section.

Hi guys,

I tried to search around but couldn't find any post with similar problem. Hopefully someone can help me here.

So, I have a 07 g35 coupe 6mt with 70k miles on it. Aside from pinging noise in low rpm (2-3k) and clutch squeak ( as countless other g35 owners are going though), I have started to hear another noise thats robbing me of my sleep.

Its in high RPM range (5-7k) and under hard acceleration. I have heard it only few times and its hard to find a pattern. Other times, the engine accelerates smoothly throughout. And other than that, there is no other abnormal engine noise.

The high rpm noise is not always there. I can't really say what it is (maybe like scratching noise) but there is no loss of power or anything. And if I let go of gas, the noise stops even though the rpms are still in that range. But if I press gas again, the noise would come again. But its not a constant noise and only happens for a bit like couple of second and stop even if I continue accelerating. I was thinking that it could be pinging but it sounds different from the ping all other are hearing. You can hear the low rpm pinging here: https://g35driver.com/forums/engine-...mt-noises.html

The noise I am talking is - I would say it more high pitched and with higher frequency. Would pinging noise increase in frequency because of high rpm?

What do you guys think it could be? Whats the worse it could be? Pls. help, I bitting my fingers off as I am out of warranty now.

And if my engine was damaged or abused (i.e. run on low oil), is it possible for it to make noise only sometime and be perfect other times? I mean how would engine sound if it was ever damaged because of low oil or redlining? I have never done either but don't know about the previous owner.

Please guys, help is greatly appreciated.

 

I've got the same issue - and just like you described, only at high RPM and under hard acceleration. I have cold air intakes, which add some volume to the engine noise period, but the seems to be a baffling/limiter/throaty noise. I even took my mechanic for ride and kept the car in lower gear to duplicate issue but he wasn't able to find ANYTHING. I've noticed past few days that on very cold days, the noise is present even at start up, low RPMs and of course, way worse under hard acceleration. Once the car warms up, I have to stop and restart engine for the noise to go away at lower RPMs, but the high rev issue is always there. I'm same boat as you, nervous of anything serious since no more warranty.

 

The noise went away on its own. In fact, in total I heard it like less than 10 times. And my car has been fine since then (knock on the wood). The only thing I did was to change oil and air filter regularly. And I use full synthetic oil. Also, I don't usually drive hard.

Was mechanic able to recreate the noise and still not sure what it is? You can always take it to infiniti and pay for their diagnostic test (about 100 buck) and maybe worth your sleep at night.

Let me know how it goes and hopefully your car will be just fine.

 

Yeah, I think the Infiniti Diagnostic may be the best thing. Mechanic rode with me as I duplicated it, which is probably what i'll do at dealer.

I sometimes think that maybe low on oil or oil getting 'spent' and if I check, it always looks great, both level and color. (which is reassuring)

If/when I take to dealer, i'll come back and post on this thread so i can update you.

thanks

 

You can also record the noise using camera and post it here. We maybe able to better help you then.

And good luck!

 

I know exactly what your talking about. High pitched ping noise when at high RPMs. I wish someone knew. 2007 g35x

 

I think I may be suffering from a similar noise. During hard acceleration or high revs if I listen very closely there is a slight scratchy/rattle noise. I'm pretty new to my current G, but my previous car (an old celica) had a similar issue which turned out to be an exhaust leak. It was more of a buzzing sound on the Celica, but I guess this could still potentially be the problem for my G, and possibly yours. I've gotten wind before of some nissans suffering from exhaust leaks near the cat, so I might peek at that to check mine out, and I guess you could do the same. I'm not a mechanic, but I like to tinker around. Just my two cents. I could certainly be completely wrong, but I thought I'd throw an opinion in there just in case.