[droftrah]

Been trying to figure this out since last week but it appears that when the AC is on there is a noticeable whine from the engine under normal acceleration. Very noticeable at 1500-2500 rpm while accelerating "normally." ie when in park and you lightly rev the engine there is a light whining noise when the AC is on but if I turn all the hvac controls off and then rev the car it sounds normal with no noise. Turn the hvac back on and then the whine is back... This definitely was not like this until the last week or 2. Any ideas?

[NWswe]

Hi,

I have the exact same problem with my m40i, ive called my dealer and he said that it could be because of the extreme heat we have had in Sweden the last couple of weeks and the AC have to work very hard. But I dont really buy this because ive never had this noise in any other car.
I have a bit of a long drive to my dealer so havent been able to go there yet, but is very intrested to hear from you or any other with the same problem if
you get any answers. Its a very annoying sound so I hope there is something that could be done to solve this.

[ParadigmDawg]

Originally Posted by NWswe

Hi,

I have the exact same problem with my m40i, ive called my dealer and he said that it could be because of the extreme heat we have had in Sweden the last couple of weeks and the AC have to work very hard. But I dont really buy this because ive never had this noise in any other car.
I have a bit of a long drive to my dealer so havent been able to go there yet, but is very intrested to hear from you or any other with the same problem if
you get any answers. Its a very annoying sound so I hope there is something that could be done to solve this.

Our heat index yesterday and probably the last 2 weeks was 112 degrees(F)and mine doesn't whine so I don't buy that.

[freitz]

Originally Posted by droftrah

Been trying to figure this out since last week but it appears that when the AC is on there is a noticeable whine from the engine under normal acceleration. Very noticeable at 1500-2500 rpm while accelerating "normally." ie when in park and you lightly rev the engine there is a light whining noise when the AC is on but if I turn all the hvac controls off and then rev the car it sounds normal with no noise. Turn the hvac back on and then the whine is back... This definitely was not like this until the last week or 2. Any ideas?

Can you record this whine?

[fxoffroad]

Is this your first BMW or have you had others?

If you've had others and it sounds significantly different than your others, I'd take it to your dealer.

If this is your first, you may just need to get accustomed to it... all mine have sounded significantly louder than other brands I've owned - especially after just starting or if its very hot.

That said, I think BMW A/C is exceptionally strong and cools quickly.

Originally Posted by droftrah

Been trying to figure this out since last week but it appears that when the AC is on there is a noticeable whine from the engine under normal acceleration. Very noticeable at 1500-2500 rpm while accelerating "normally." ie when in park and you lightly rev the engine there is a light whining noise when the AC is on but if I turn all the hvac controls off and then rev the car it sounds normal with no noise. Turn the hvac back on and then the whine is back... This definitely was not like this until the last week or 2. Any ideas?

[droftrah]

Originally Posted by freitz

Can you record this whine?

Not sure how well it will record but I'll give it a shot.

Originally Posted by NWswe

Hi,

I have the exact same problem with my m40i, ive called my dealer and he said that it could be because of the extreme heat we have had in Sweden the last couple of weeks and the AC have to work very hard. But I dont really buy this because ive never had this noise in any other car.
I have a bit of a long drive to my dealer so havent been able to go there yet, but is very intrested to hear from you or any other with the same problem if
you get any answers. Its a very annoying sound so I hope there is something that could be done to solve this.

Glad I'm not the only one! I plan on bringing it up at the dealer when I take her in for the first oil change in about 1000 miles. Will continue to monitor it until then.

[droftrah]

Originally Posted by fxoffroad

Is this your first BMW or have you had others?

If you've had others and it sounds significantly different than your others, I'd take it to your dealer.

If this is your first, you may just need to get accustomed to it... all mine have sounded significantly louder than other brands I've owned - especially after just starting or if its very hot.

That said, I think BMW A/C is exceptionally strong and cools quickly.

I've had others and my old F25 X3 I would notice a similar noise when staring up the car on a hot day and blasting the AC, however the noise would always go away after a few minutes of driving and this only occurred sometimes. This whine occurs continuously regardless of outside temperature, engine temp, fan speed etc. when the AC is on it always whines which is why I'm concerned. Plus it makes the engine note sound like crap...

[freitz]

Originally Posted by droftrah

Not sure how well it will record but I'll give it a shot.



Glad I'm not the only one! I plan on bringing it up at the dealer when I take her in for the first oil change in about 1000 miles. Will continue to monitor it until then.

I have a noise that I can't explain in my x3 M40i. The best way I found was to mount a go pro in the car and record for about an hour or two different roads etc...

[Tjalle]

Two possible sources I can think of:
-clutch/compressor "noisy" - since new noise something happened - "shit"?

-"compressor" belt - allpurpose belt, but more strain when compressor working.

Dealer should be able to sort out.

[iamthestig]

Add me to the list. At first, I thought it was coming from the HVAC itself, but then realized it only occurs when the A/C compressor is running. It takes a few moments after the A/C button is turned off before the compressor stops, but the noise definitely goes away. Very obvious and annoying.

[NWswe]

I went to my dealer yesterday and had a technician listen to the whining sound, and it should definitely not be there.
He could not say exactly what it was but they are goning to take it in 28th of June and fix it. I will let you know as soon as the problem is gone.

[nlk10010]

Does the "noise" rise and fall with engine RPM?

I started a thread a while back about a similar phenomenon, only happens with A/C compressor on and tracks engine RPM. But to me it's not coming from the engine; rather, it's almost like an electrical whine CAUSED by the engine, perhaps by the ignition system (do cars these days even HAVE an ignition system? ).

I will probably bring it in but my fear is that in order to troubleshoot/fix they'll need to remove the dash, which is NOT happening.

[iManu]

I have this issue with my car. Only does it when the ac kicks in.

[droftrah]

Originally Posted by nlk10010

Does the "noise" rise and fall with engine RPM?

I started a thread a while back about a similar phenomenon, only happens with A/C compressor on and tracks engine RPM. But to me it's not coming from the engine; rather, it's almost like an electrical whine CAUSED by the engine, perhaps by the ignition system (do cars these days even HAVE an ignition system? ).

I will probably bring it in but my fear is that in order to troubleshoot/fix they'll need to remove the dash, which is NOT happening.

Yep, the whining tracks the rpm usually only noticeable under 3000 or so because the engine sound overpowers the whining above that.

Going in for an oil change tomorrow morning and will mention it but I'm going away tomorrow night so I need the car back. Also with the excessive heat here in the mid atlantic US the AC has been running overtime and the whine seems to have fixed itself a little because of it, the past couple days I can't really notice it and can't tell if its still there... Go figure

[Scout10]

what years and how many miles on the noise vehicles.
noise is it a whine , screech , buzz , scrape , . . . . . . . . . . or mother in law (had to !)

is there a vibration associated with noise, . . . . . . at compressor ?

[droftrah]

Originally Posted by freitz

Can you record this whine?

Finally remembered to do this the other day:

The audio isn't great but you can definitely hear the difference in the "whine" from the engine, i.e. the whine is apparent in the AC on clip and the engine is barely audible at all in the AC off clip. Recorded in moderate traffic on a busy road at rush hour in the afternoon, low speed driving, shifting between 2nd and 4th gear, speeds between 10 and 35 mph. I was about 10 min into my commute so the car was at operating temp, cooled off inside, and HVAC temp set to 70F auto mode, mid fan speed, outside temp ~80F, comfort mode - quiet exhaust mode.

With AC on (auto mode, fan speed in center):

https://ufile.io/1ptyv

With AC off (same conditions as above just tapped the A/C button off and waited 5 min for the compressor to shut down and hot air to start blowing):

https://ufile.io/sbd5e

[NWswe]

Just got a call from my dealer and they have ordered a new ac compressor, and they will change it as soon as they get it in. I hope this will fix it.

[freitz]

Mine doesn’t whine but it makes a noise past level 2.

[ooshnoo]

Originally Posted by NWswe

Just got a call from my dealer and they have ordered a new ac compressor, and they will change it as soon as they get it in. I hope this will fix it.

Did you get it fixed? I've got the same issue.

[M40iG01]

I have the same whine on my x3 m40i. I believe this is completely normal and is a characteristic of the particular compressor they are using on the x3. there is a new refrigerant being used and this particular compressor is very powerful and large hence the reason you can really hear it working. in other words the x3 has amazing ac if you happen to get a good one off the assembly line. the first x3 I took delivery of had no ac all. (refrigerant didnt get put in a factory or it leaked out on it's way to the dealer ) current x3 ac is great.

[NWswe]

Originally Posted by ooshnoo

Did you get it fixed? I've got the same issue.

They changed the AC compressor but the noise is still there.
They also test drove a couple of other m40i just to compare and they had the same whining noise. Unfortunately their conclusion is that the noise should be there.
So I guess we have to live with it..
But If anyone come up with a solution please let me know.

[weez]

Any resolution on this for anyone? I've noticed the whine that sounds like an electrical noise that correlates with engine RPM when the AC is on. It's pretty annoying. I guess I will add it to the list for the dealer to look at during its first servicing...along with intermittent passenger side blind spot monitoring and brake squeal.