Loud fan noise

[trhee]

i'm driving a 2003 330ci and have noticed over the past month (hot weather) that there is a loud whirring noise corresponding to throttle input...

the service tech at my dealer who went on a test drive with me said this was the secondary fan that comes on when the engine gets hot... he seemed to think that the loud fan noise coming from the engine bay was quite normal... the noise is very audible even with the windows rolled up...

anyone have any input on this matter?

also, on another matter... my check engine light has come on again... 2 days after it was serviced for the first check engine light which turned out to be a bad air flow sensor... this is my 3rd bmw and so far i'm not too keen on this latest one... my other 2 were extremely reliable with absolutely no problems whatsoever...

later,
thomas

 

[PuShAkOv]

It is much loader than in normal cars... so it could be normal.. personally I love the resonance... it spells POWER!!

 

[mallards]

dont worry about it man ... same thing happens to me whenever i sit at the bank for a while or at a red light (and its 100F outside =) ) .. the engine sounds like its almost gasping for air ... the noise usually stops on average before i get to 5th gear

and yes its the aux. fan in the engine bay

hope this helps

Ben

 

[PerfBMW328i]

The fan noise is quite normal. Most BMW 6 cyls have clutch driven main fans to cool the engine. When the temp rises the clutch is fully engaged which means the fan is rotating the same speed as the main crank. The noise is also relative to the speed. The fan clutch releases as the engine gets cooler and less noise when the car is moving!

I have a 1999 328i which surprisingly has an electric main fan which is relatively quite.