Identify My Fan Noise....Worried to drive

bdsmitty88 · 29th June 2012, 17:52

I noticed my fan making this loud, constant buzzing noise yesterday. MY 2000 M5, 59K miles

Something to note. It was by far the hottest day i have experienced since owning the car. 104 F yesterday, so It could just be that I have never heard the fan working that hard. Also, my ambient temp sensor was reading about 14F over actual all day yesterday, and it is usually spot on. So, does this temp sensor have trouble reading high heat, and does the ambient rating factor into the fan speed or is it all engine temp related?

Is this noise of concern? Thanks!

http://s1160.photobucket.com/albums/q489/bdsmitty88/?action=view¤t=VIDEO0065.mp4

bcampbe7 · 29th June 2012, 18:10

I believe that is the sound of your aux. fan (in front of radiator). You can see it through the kidneys. Mine sounds like that too when it is hot outside, so I hope it is normal.

bdsmitty88 · 29th June 2012, 18:22

Quote:

Originally Posted by bcampbe7

I believe that is the sound of your aux. fan (in front of radiator). You can see it through the kidneys. Mine sounds like that too when it is hot outside, so I hope it is normal.

Haha, yes i know it is the aux fan

I have never heard the buzzing sound that it is creating (only seems to do it when spinning at really high speed). It is louder than the video lends on too. I actually though, for my entire drive home, that there was construction echoing in the distance...but it was my fan.

Mfreakin5 · 29th June 2012, 18:22

sounds like....a fan? I don't get your question? You show a video of your fan running and are worried about fan noise? The main fan is pretty loud and the aux fan in the bumper is loud too. Don't worry unless you hear the main fan spinning really fast at high rpm's or a squeaking noise from the fan clutch area. If you're worried that your coolant temp sensor or thermostat aren't functioning properly then search regarding the secret menu OBD functions and you'll see how to check the actual values that the sensor is recording. On a hot day, however, expect there to be a lot of fan noise, its normal.

Happy motoring.

bimmerule · 29th June 2012, 18:25

Quote:

Originally Posted by bdsmitty88

Also, my ambient temp sensor was reading about 14F over actual all day yesterday, and it is usually spot on.

That is normal, the pavement surface temperature from radiant heat is usually higher than official reported temperature.

PatrickW · 29th June 2012, 18:31

All of my cars have sounded like that when the AUX fan is running at full capacity, also alerts your friends when it sounds like a 747 is in their driveway

bdsmitty88 · 29th June 2012, 18:32

Quote:

Originally Posted by Mfreakin5

sounds like....a fan? I don't get your question? You show a video of your fan running and are worried about fan noise? The main fan is pretty loud and the aux fan in the bumper is loud too. Don't worry unless you hear the main fan spinning really fast at high rpm's or a squeaking noise from the fan clutch area. If you're worried that your coolant temp sensor or thermostat aren't functioning properly then search regarding the secret menu OBD functions and you'll see how to check the actual values that the sensor is recording. On a hot day, however, expect there to be a lot of fan noise, its normal.

Happy motoring.

Yes, it is a fan, yes it is spinning, but the tone of the noise was what had me concerned. It sounds like a lawnmower going. I have never heard the fan make that sound, so I was just wanting to check that it was a normal tone, and normal volume.

Also, no chance of hearing the fan spin at high rpms with my muffler delete.

I know about the cluster menu, and I have checked Ktemp many times. I was just under the impression that ATEMP on the secret menu was the same reading that displays all the time on the cluster and on the Nav

bcampbe7 · 29th June 2012, 18:34

I pulled up to the to-go parking at a local Mexican restaurant the other day, which happens to be right next to the outdoor seating area. Funny seeing the folks sitting there quickly look at the car thinking they are about to be sucked into the vortex. LOL

bcampbe7 · 29th June 2012, 18:35

Quote:

Originally Posted by bdsmitty88

Yes, it is a fan, yes it is spinning, but the tone of the noise was what had me concerned. It sounds like a lawnmower going. I have never heard the fan make that sound, so I was just wanting to check that it was a normal tone, and normal volume.

Also, no chance of hearing the fan spin at high rpms with my muffler delete.

I know about the cluster menu, and I have checked Ktemp many times. I was just under the impression that ATEMP on the secret menu was the same reading that displays all the time on the cluster and on the Nav

The Atemp may be yet another temp sensor in the DME area and related to the e-box fan working or not. Sailor may have more input on that.

bdsmitty88 · 29th June 2012, 18:38

Quote:

Originally Posted by bcampbe7

The Atemp may be yet another temp sensor in the DME area and related to the e-box fan working or not. Sailor may have more input on that.

I recall reading many conflicting statements on the origin of the ATEMP reading before, some saying it was a mix of things maybe

I don't particularly recall if ATEMP is strictly ambient temp, or inlet air temp...or both!!