Weird noise in engine bay ... whir whir whir intermittent
08-10-2013, 07:37 AM
#1
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Weird noise in engine bay ... whir whir whir intermittent
Hey guys - here's a fun one. Anyone have any ideas?
I'm guessing secondary air pump or the eblower motor ... and also read a thread about the oil filter house mounts wearing the resting against something, causing this noise as the oil is pumped (long shot).
Turning on and off fan has no affect. AC no affect. Changing vent settings has no affect. Can't hear it when driving, as the motor cancels it out, but I'm sure it's still there.. also doesn't seem to be affected by RPM's. As I accelerate, the sound is noticeable until the engine cancels it out, but, the sound does not increase in oscillation frequency.
Have a listen to the video... it's the whiirrr.......... whirrrrr.......... whirrr.........whirrr......whirrr.. noise... sounds like a sick wiper motor.
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2004 545i - auto trans.. standard suspension.
I'm guessing secondary air pump or the eblower motor ... and also read a thread about the oil filter house mounts wearing the resting against something, causing this noise as the oil is pumped (long shot).
Turning on and off fan has no affect. AC no affect. Changing vent settings has no affect. Can't hear it when driving, as the motor cancels it out, but I'm sure it's still there.. also doesn't seem to be affected by RPM's. As I accelerate, the sound is noticeable until the engine cancels it out, but, the sound does not increase in oscillation frequency.
Have a listen to the video... it's the whiirrr.......... whirrrrr.......... whirrr.........whirrr......whirrr.. noise... sounds like a sick wiper motor.
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2004 545i - auto trans.. standard suspension.
08-13-2013, 07:19 AM
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My Ride: 545
It does sound like a wiper motor . 
Weird have not heard that one before without having wipers on . Have you tried to isolate where the sound is coming from ? I guess you have to some extent .
Weird have not heard that one before without having wipers on . Have you tried to isolate where the sound is coming from ? I guess you have to some extent .
08-13-2013, 07:24 AM
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I'm going to drop by my indy shop next time it does it and see if they can help isolate it with a 'scope. Seems to be close to the firewall, passenger side. I'm thinking secondary air pump.. maybe.. ..maybe ac bearing (but it was brand new last year).. hmmmm.
08-13-2013, 07:29 AM
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fyi - waterpump, pulley and belt is all new. Just did the coolant transfer pipe not too long ago. PCV valves are new too. Could this be an air leak? Mechanic said the crankcase pipes/hoses were on their last legs... on had a small crack.. he taped it up to give me time to order (I'm slow.. that was a month ago.. it's now on order). ...however, I highly doubt this sound is coming from a cracked crankcase vent pipe..