Dentist Drill noise at 2500RPM+
 

Hi everyone,

I have a 2009 Mini S, manual transmission. A while back i brought my Mini into my dealership because I was having an ANNOYING rattle which I finally found the solution to in one of the posts here on NAM. The problem was the wall to the right of the gas pedal. It was vibrating at certain RPMs. I'm not sure what they did to fix it, but ever since I picked it up from that service appointment, it has had an engine noise that sounds like a high-pitched whine/dentist drill type noise. It is really audible beginning around 2500RPMs and continues to increase in amplitude as the RPMs increase. It actually makes me nervous (but they assure me that it is not dangerous in any way).

- I immediately brought it back in, they told me it was my timing chain, that it was all stretched out. It wasn't the source of the noise though.

- I brought it back and took a ride with the head technician. He said he's heard it before, they took it back in, replaced the water pump. Noise was still present. They said they put silicone in the line and that the silicone should work its way through and take care of the noise. It never did.

- Brought it back a few months later, when it was up for a brake fluid flush. They replaced the friction wheel. Noise is still present.


This is my second Mini, my first was a lemon that nearly killed me, and I seem to have endless trouble with this new car as well. I am extremely frustrated! Can anyone make any sense of this?? I would greatly appreciate it!

Thank you!

At 25,000 rpm you are probally hearing your MINI preparing to take off.

i have the same problem and have an appointment for sat to drop it off! if you turn the wheel slightly on mine it goes away for a sec. noticed it after being in for a timing chain issue.

Typically on a turbo car...hearing a dentist drill noise is a sign the turbo is shot or on its way out...

Thanks Thumper!! once again lets hear it for extended warranty!!!

Sure it's not the AC compressor?

nope no ac was on when Smurf was rolling to halfmoon bay. windows open and stereo off to pinpoint sound

flywheel bearing?

dentist drill = turbo going. 2500rpm's is probably about where you're starting to see boost, either compressor or turbine wheel.

how many miles do you have?

hey, check the heater unit, I myself too went to two trips to the dealer n no luck so I took it apart to fix it myself.

the heating unit n the housing is what rattles at 2300rpm on my car, in cold morning makes noise then when the car warms up, it settles.

I hope this helps, u can try telling the dealer to fix it, but i think it will come back unless they change the whole unit as one

Matt

:roll: Way to throw out there a horrible catastrophic failure when theres a ton of things that can make that noise







Single out components-



Is it rpm only dependant?

Are you in motion or can you replicate this sound free revving?

Are you under load(accelerating)?

A/c on or off?

Wheel speed dependant?

Selected gear dependant(this can point to faulty trans bearrings)?

Single out components and it will be easy to narrow your issue down.

Coming from the VAG world (which Erik and I both were from)...when someone posts saying they hear the dentist drill noise @ 2500rpm, its the turbo. No if's, and's, but's about it...

He asked for opinions on the problem and I know what I'm going with....

I cant agree with you there, too many rotating bearings that can produce that noise. With the little information about what the exact symptoms are



you cant just point a finger:no:


edit* You gave an opinion, erik states that is what it is... big difference also



If th OP is able to go up to the same rpms as the complaint and still gets that noise you can almost exclude the turbo because you will not be in boost/ turbo will not be at the underload shaft speeds as when in boost which would create the sound.


Now if he goes up to the complaint engine speed and no noise is prevalent but when there is load/boost there is, then you can norrow it down to turbo issues.


But not off the bat:nod:

Okay, sorry, excuse me. It maybe the turbo going, that would be MY guess and my opinion, not a fact. When described as a dentist drill, usually you are pointed to the turbo, again, only in my opinion.
If it was a high pitched whine that increased with RPM, and they had just fixed a rattle somewhere by your footwell, then I might say that it could be a bad ground, since they may have messed with wiring/disconnected/reconnected electrical components. A bad ground will cause a high pitched whine that increases with RPM, because of the alternator. This is common when people do aftermarket stereo installs. Again, that is just my opinion.
If you have recently installed a "cold" air intake (or any open intake filter) that removes or opens up your airbox, when you're accelerating you'll hear a high pitched whine/whistle as well. However, this is just my opinion, and that of some (many) others on this forum, assuming that their posts on other threads reflect their opinions.

Good luck diagnosing.

Lol:lol: dont take it like that,




The stereo ground whine is a good thing to look in to as well +1 to that.