Here's an observation I had in our long-term 2002 BMW M3 over the weekend.
The fan delivers air to the cabin with a peculiar whooOOSH.... whooOOOSH... whooshwhooshwhoosh...
. whooOOSH sound that is especially prominent in the first 5 mins after the car is started.
Anecdotally, the climate control system in my old E36 M3 did this exact same thing before it had a massive freak-out and stopped working entirely.
Sign of impending demise, or "it's normal, they all do that"? Stay tuned.
Jason Kavanagh, Engineering Editor @ 58,042 miles.
crazie88 says:
01:20 PM, 06/30/08
My 02 325i did the same thing. It always annoyed the heck out of me. Even worse when it blows hot air out, then you're frantically trying to lower the fan.
SubyTrojan says:
01:50 PM, 06/30/08
If the system begins having problems blowing cool air, the final stage resistor may be ready to kick the bucket. They were replaced fairly often at the BMW dealership I used to work at.
http://forum.e46fanatics.com/showthread.php?t=256286
m_thrizzle says:
02:27 PM, 06/30/08
I'm not sure if you are referring to the auto fan going full blast when you first start the car and it tries furiously to cool down the car to the desired temp, or if the fan is going haywire. SubyTrojan is right though, if the blower seems to have a mind of its own, replace the F.S. Resistor.
You can manually control the fan speed if Auto mode is annoying.
Also, the button with the two circles, one of which contains an 'A', is for outside air/recirculate. If the left light is on, it's in auto mode and will supposedly switch to recirc if it detect odors.
jkavanagh says:
02:46 PM, 06/30/08
The oscillating whoosh, which is what I attempted to describe above (apparently unsuccessfully), occurs whether in "Auto" mode or not.
Air blows cold.
empowah says:
03:22 PM, 06/30/08
I think it's the final stage, too.
banhugh says:
04:03 PM, 06/30/08
whooOOSH.... whooOOOSH... whooshwhooshwhoosh... whooOOSH
It sounds like my dog.
roadburner says:
10:34 AM, 07/ 1/08
Yep, it's the FSR.