whining belt sounding noise at highway speed
 

Hey guys i'm looking for some help....my Z is out of warranty and im at 31k miles. At lower speeds (<50ish mph) my Z sounds normal, as in good exhaust noise and motor noise. Once I start to speed up and I am on the highway, i'm getting like a belt whining noise and its to the point where if i'm in 6th gear and give it just a little gas or even if i downshift to 5th to speed up a bit, I dont even hear the exhaust or motor, all I hear is a whining noise and it sounds terrible. Whats weird is that if I go through a puddle it seems to get worse...could this be a really bad wheel bearing issue or does it sound like possibly and intake problem?? Like i said im out of warranty and the dealership wants $120/hr :thumbsdown: Any help is greatly appreciated!!

I believe it is ECU whine, not a belt

Have you checked your supercharger?

Take a passenger along for a ride and see if they can pinpoint the source.

As per DE.50, it could be the ECU (right side footwell). Could be the tires. I doubt it is a wheel bearing - they tend to have a "gritty" rumble/growl instead of a whine.

Edit: could also be the fuel pump.

Are you driving in ... reverse?

:inoutroflpuke:

i just did some research into what the ecu would sound like and from what I understand is that it would be a high pitched frequency noise. Mine is not like that. When i touch the gas or when i have cruise control on I dont hear exhaust or anything, I just hear like a belt noise.

Can the belt , fan be moved by hand without tools?

Is it related to engine speed then? if so then that rules out everything like wheel bearings and tires.

If you are not moving and you rev up the engine do you hear the same sound?

no its only when im moving and at higher speeds >50 mph. the noise drowns out all other noises and just whines. It started this winter so I didnt know if the car just doesnt like cold weather or what but it sounds bad.

you call DE?

Could be a lot of things, including trans or diff. You need to pinpoint the location of the noise.

probably not engine related... might be tranny related, but not sure if op tried going up to 7k rpm in 1st. that'll net you sub-50mph noise.

no noise, then probably wheel bearings or something.

something like over excited squirrels residing inside intake... :ugh: .. or a/c inlet vent area.. :ugh2:

find acorns on your cabin filter? :ugh:

Does your car have a 3M bra on the front of it?

What about if you pop the car into neutral while moving and let the engine rpms go to idle, is the noise still there?

the noise only exists when im on the gas

Could be the injectors. Or maybe just a loose piece of sheet metal that is vibrating. Until you can come up with a more specific location, we're just shooting in the dark.

even in neutral?

He said earlier it was when only when moving upwards in the 50mph range.
I am thinking a bearing somewhere along the drive train. Transmission or rear end.

ill have to check if it makes the noise in neutral while rolling if i rev it. But if im going and and i let off the gas while in gear still it stops making the noise. Ill try and pin point the noise better but it sounds like its just the whole car.

You can put the vehicle in neutral while rolling you know :)

I suppose.

I am thinking a bearing under load is getting forced into a not so happy position.

Thats why neutral was suggested, then you would have no load on the drivetrain and it would just be free spinning. I guess that would not eliminate say an output shaft bearing or anything like that but it would be a start.

from my experience with prematurely worn bearings they make noise regardless of engine input. progressively louder in highway speeds...and the entire car does resonate like a DC10... :eekdance:

i could tell from which corner it was coming from so told the dealer to check and they said my ear was right on.

Hellow sorry for my english im spanish.

Do you finally know were the sounds come?

I have the same problem and the dealership don't know where it comes.

thx!!

Belt Whine, 2010 370Z
 

Well, I think its a belt whine. Its not my supercharger belt (haven't got one a them).

When it happens: After fully warmed up and higher than idle RPM. Occurs sitting parked, in neutral or driving, clutch engaged or not, doesn't matter, follows engine speed.

I think I'll grease up the belt and see if that helps. I'm gonna use Hog Fat. That's the right stuff ain't it?

thanks for any suggestions or ideas.