Belt or Pulley noise
#1
I'm getting a noise from the front end accessories that I am trying to diagnose. Any feedback will help me decide if I should bother going to the dealer and have it looked at to be taken care of under CPO or just have an indy that would be closer and less hassle deal with it. Here are the specifics.
05, 545i auto
sounds like a slipping belt squealing noise but trying to rule out a bearing or dying accessory
ambient temperature has been around 30-40
only seems to happen below 1000 rmp and seems to stops once the car returns to idle. I notice it off throttle while coasting to a stop. A blip over 1000 rmp and it stops until it passes back through that range on its way to idle, once at idle for a little bit it fades out.
only seems to happen once the car is warmend up and driven more than 20 miles
Normally I would assume its a belt because of how it sounds. From experience belts squeal when they are cold and it goes away when its warm, this is the opposite which makes me think it is more mechanical.
I tried to adjust the belt myself but once I go all the covers off I was lost. Long gone are the days when you can just pull up on the alternator to tighten it all up. Belts seem tight but I know they will still slip when they feel taught, just ruling that out.
Thanks
05, 545i auto
sounds like a slipping belt squealing noise but trying to rule out a bearing or dying accessory
ambient temperature has been around 30-40
only seems to happen below 1000 rmp and seems to stops once the car returns to idle. I notice it off throttle while coasting to a stop. A blip over 1000 rmp and it stops until it passes back through that range on its way to idle, once at idle for a little bit it fades out.
only seems to happen once the car is warmend up and driven more than 20 miles
Normally I would assume its a belt because of how it sounds. From experience belts squeal when they are cold and it goes away when its warm, this is the opposite which makes me think it is more mechanical.
I tried to adjust the belt myself but once I go all the covers off I was lost. Long gone are the days when you can just pull up on the alternator to tighten it all up. Belts seem tight but I know they will still slip when they feel taught, just ruling that out.
Thanks
#2
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Don't these engines have serpentine belts?
#5
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My Ride: 2004 BMW 545I
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I'm getting a noise from the front end accessories that I am trying to diagnose. Any feedback will help me decide if I should bother going to the dealer and have it looked at to be taken care of under CPO or just have an indy that would be closer and less hassle deal with it. Here are the specifics.
05, 545i auto
sounds like a slipping belt squealing noise but trying to rule out a bearing or dying accessory
ambient temperature has been around 30-40
only seems to happen below 1000 rmp and seems to stops once the car returns to idle. I notice it off throttle while coasting to a stop. A blip over 1000 rmp and it stops until it passes back through that range on its way to idle, once at idle for a little bit it fades out.
only seems to happen once the car is warmend up and driven more than 20 miles
Normally I would assume its a belt because of how it sounds. From experience belts squeal when they are cold and it goes away when its warm, this is the opposite which makes me think it is more mechanical.
I tried to adjust the belt myself but once I go all the covers off I was lost. Long gone are the days when you can just pull up on the alternator to tighten it all up. Belts seem tight but I know they will still slip when they feel taught, just ruling that out.
Thanks
05, 545i auto
sounds like a slipping belt squealing noise but trying to rule out a bearing or dying accessory
ambient temperature has been around 30-40
only seems to happen below 1000 rmp and seems to stops once the car returns to idle. I notice it off throttle while coasting to a stop. A blip over 1000 rmp and it stops until it passes back through that range on its way to idle, once at idle for a little bit it fades out.
only seems to happen once the car is warmend up and driven more than 20 miles
Normally I would assume its a belt because of how it sounds. From experience belts squeal when they are cold and it goes away when its warm, this is the opposite which makes me think it is more mechanical.
I tried to adjust the belt myself but once I go all the covers off I was lost. Long gone are the days when you can just pull up on the alternator to tighten it all up. Belts seem tight but I know they will still slip when they feel taught, just ruling that out.
Thanks
you cannot adjust the alternator belt because it is held by a tensioner. my guess would be the alternator bearing or the pulley attached to the alternator. good luck and when you have the problem solved...please let us know the outcome.
#6
a lot of times the tensioner pulleys go bad. to check, run the engine and using a long screwdriver, touch the tip to different areas that you think might be the culprit and put your ear to the handle. the sound will transmit through the handle. be careful no to touch any moving parts though
#7
a lot of times the tensioner pulleys go bad. to check, run the engine and using a long screwdriver, touch the tip to different areas that you think might be the culprit and put your ear to the handle. the sound will transmit through the handle. be careful no to touch any moving parts though
#8
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My Ride: 2007 530i Sport Alpine White, winter package, comfort access, bluetooth, Satellite radio, tinted windows, Michelin Pilot Sports PS2s
Use a hose or Tyon tubing to determine where the noise is coming from. Hold one end to your ear and the other to the possible sources. You'll find this works well.
#9
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My Ride: 2004 530 Steptronic, Nav, Std Audio w/ single CD, Premium Pkg, BMW Assist, non-working Bluetooth
As some have noted, among the prime suspects are the idler pulleys and/or the alternator. Mine died a year ago -- about the same age as your car. Good luck!
#10
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My Ride: 2004 BMW 530i - no mods. Pretty basic really. I mean it has tires, windows, and a sweet look, what more could a man want? Honestly, I'd like to improve the sound system mildly, and possibly find a worthy engine mod that would increase my BHP by 100 without giving an arm and a leg for. I don't think it's out there, so I'll stay stock and love driving my 530i.
I was getting a lot of belt noise on my CPO 2004 530i and the dealer replaced it under the CPO coverage. Take it in and see what they say...