Faint, high-pitched whistling sound

[Lorico]

This happens to me too only when the engine is cold. As soon as it gets to its operating temperatures I can't replicate it.

[FRS-Learner]

I get it when I drive on 5+ hour trips. It's exactly what you guys say it is, like a gear whine. If I'm on the throttle then there is a whine. If I apply more throttle it gets louder. It's quite annoying on long trips, but I think my head just tones it out. No mods whatsoever.


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[toeout]

- It seems most noticeable in 6th and 4th, but it's also there in 5th , just quieter. Makes make think that it's present in all gears, but you really notice it when your speed is steady.


- Noise is gone when taking it out of gear on the hwy at 60-70 mph and revving the engine.


- I have an aftermarket intake and the soundtube is disconnected from the intake and the opening sealed with an aluminum foil, so definitely not the source


- I had my steering wheel replaced at the dealer in the week the noise started, but I can't possibly see the connection.


- the noise is louder, different pitch and affects much broader rev range than the diff whine. I got the Whiteline inserts on the rear subframe and there's very subtle diff whine at 65-70mph in 6th gear.

[cdq85]

did you buy your car used? perhaps the previous owner installed whistle tips. might want to check. in case you aren't familiar...

[ame="https://www.youtube.com/watch?v=eSOSJ68xOBA"]Whistle Tips with Bub Rub - YouTube[/ame]

[Wyattkb]

Anyone ever figure out what makes this noise?

It is so loud at exactly 80MPH, if I accelerate to 81-82MPH its much more quiet or decelerate below 80MPH.

Also, the noise is much more apparent when looking out the windshield versus turning my head to the left or right while sitting in the driver seat.

I am contemplating just replacing all the bushings with much firmer ones, if the car is already this loud I might as well get some performance gains from stiffer ones.

My daily commute is 40 miles on an interstate, so I am constantly at the 75-80MPH range. I don't know how much more I can take.

[inio]

Originally Posted by Wyattkb

Anyone ever figure out what makes this noise?

It is so loud at exactly 80MPH, if I accelerate to 81-82MPH its much more quiet or decelerate below 80MPH.

That's a separate issue than is being talked about here. The issue here is a constant tone at a wide range of speeds, related to throttle/power/rpm. If you've got the same thing I've got its not (or mostly not) related to throttle and only related to speed.

Edit:Here's the right thread.

Mine happens around 69-70mph, and I can also hear it a bit at 35mph. It seems like it's toward the rear of the car, and the pitch does NOT seem to vary with speed (and over the 2mph range I can hear it it should cover ~10JNDs of pitch). My current theory is a harmonic of the wheel spokes driving a high-Q resonance somewhere, but I haven't gotten a clean measurement of the tone frequency or done the math on the spoke frequency.

Can you hear yours at 40 at all?

[orangeblue]

Originally Posted by unlimited86

I just notice mines today, Only happens when I am in 6th gear and at least 3k rpm, it gets louder when i get it up to 3.5k and the sound will go away if i let off throttle and will come right back when Im on it. Does not happen in other gears and I would say its more of a whining sound, its going to be irritating going on long road trips.

Same here. Since it's only 6th gear, it's got to be transmission related.

[ZeHeadBanger]

I too recently heard this sound on my car while driving on the interstate. I've heard this noise only a couple of times in my car but this is what I noticed:

- Happens only when the vehicle is in the 6th gear
- Happens only when I'm on throttle, it goes away when I let off throttle
- Have heard the noise only above 3,000-3,500 rpm

It sounds more like a gear whine, but maybe called a whistling noise too. When I heard this noise the first time I really thought one of my windows was not fully closed (if this gives you an idea as to how the noise sounds). The other thing was I recently cracked my front windshield above the rear view mirror mounting point and I thought that may be the source of the wind noise, but nope, then it should happen in all gears. The whine is a faint high pitched tone.

It's making me think it's a gear related issue. I don't think this is an 'issue', it's just something that we may have to live with.

Anything else you guys suggest I should check other than the ones mentioned in this thread? FYI, I'm running a Perrin Catback exhaust as my only mod (other than tires and brake pads). But I have been running this for almost a year now.

[AreteAuto]

Guys, this sound is completely normal. I believe it comes from the differential, and I actually enjoy it. If it's getting too annoying, you could check the diff bushings, but it is absolutely nothing to worry about. You'll notice the same sound from e46 gen 3-series BMW's, that's my only experience with a car that whines a bit.
But, I repeat, this is normal and nothing to worry about. I was actually considering getting a solid diff-riser to eliminate the rear axle-angle issue, but a solid mount would magnify that whine like a racecar.
This is what it sounds like magnified at lower speeds:
[ame="https://www.youtube.com/watch?v=I1NTNzWBFy0"]FR-S Differential Riser Sound - YouTube[/ame]

[orangeblue]

Originally Posted by AreteAuto

Guys, this sound is completely normal. I believe it comes from the differential, and I actually enjoy it. If it's getting too annoying, you could check the diff bushings, but it is absolutely nothing to worry about. You'll notice the same sound from e46 gen 3-series BMW's, that's my only experience with a car that whines a bit.
But, I repeat, this is normal and nothing to worry about. I was actually considering getting a solid diff-riser to eliminate the rear axle-angle issue, but a solid mount would magnify that whine like a racecar.
This is what it sounds like magnified at lower speeds:

I can't recall seeing anything about a noise like that on e46fanatics, and I was on there the entire 7 years I had my ZHP. Either way, the noise I have occurs exclusively in 6th gear, so not at low speeds.

[chaoskaze]

sometime this car just makes so much noise that i don't know what's going on. =.=

Was pushing the car in GMR yesterday, then i noticed my engine sound really different.... let the car rest a bit then it sounds the same again........

[AreteAuto]

Originally Posted by orangeblue

I can't recall seeing anything about a noise like that on e46fanatics, and I was on there the entire 7 years I had my ZHP. Either way, the noise I have occurs exclusively in 6th gear, so not at low speeds.

The noise is so prominent on our e46's that they probably don't even question it.
On our cars, it is much more noticeable in 6th gear. Specifically at interstate speeds, if you feather the gas pedal, you will hear it go on and off. You can't hear it at lower speeds because the differential is not spinning near as fast. In the video I posted, the differential is on a solid mount, so the sound is magnified, making it audible at all speeds.
If you feel like looking into it, go ahead, but I do promise it is normal.

[dphee79]

Has anyone figured out yet? Is it really something I have to live with? This started happening and driving me crazy. It is so annoying. My mpg went down by 2-3 mpg too.

[Norinradd]

I was googling as im getting this. Along with p0420 code and catless header. Mine is only while starting off, first or second. At 1000-3000rpm, It does sound like a trans gear whinding up weird to me but have to stop being so paranoid, have a feeling these cars will last a long time.

Anyways heres a good link!

http://www.theglobeandmail.com/globe...service=mobile