Whining on cold start

[G05V8]

Hello, ever since it started getting colder I noticed when its 35 degrees or less my wifes F15 N55 driving from a cold start has a whining noise which fluctuates with RPM but tends to go away once the car is warm. I've had my transmission pan/fluid replaced a few months ago as well my serpentine belt along with idler pulley so I can pretty much rule out 2 common possible issues. Anyone else who reside in colder climates have this as well?

[///d]

Originally Posted by G05V8

Hello, ever since it started getting colder I noticed when its 35 degrees or less my wifes F15 N55 driving from a cold start has a whining noise which fluctuates with RPM but tends to go away once the car is warm. I've had my transmission pan/fluid replaced a few months ago as well my serpentine belt along with idler pulley so I can pretty much rule out 2 common possible issues. Anyone else who reside in colder climates have this as well?

Could be a few things.

If it's a loud squealing sound you need to re-adjust your belt.

You could be hearing the power steering pump trying to move cold fluid, especially if you hear the whine change pitch when you turn the steering wheel, and since you recently replaced the belt it may need some tension adjusting to help the pump. That usually happens when it's much colder though.

If it's a whine through the speakers then you have a ground issue somewhere on the vehicle. You can usually rule that out by turning the stereo completely off and see if it stops, but with the iDrive system I don't know if that works.

[G05V8]

Originally Posted by ///d

Could be a few things.

If it's a loud squealing sound you need to re-adjust your belt.

You could be hearing the power steering pump trying to move cold fluid, especially if you hear the whine change pitch when you turn the steering wheel, and since you recently replaced the belt it may need some tension adjusting to help the pump. That usually happens when it's much colder though.

If it's a whine through the speakers then you have a ground issue somewhere on the vehicle. You can usually rule that out by turning the stereo completely off and see if it stops, but with the iDrive system I don't know if that works.

Thanks for the reply! I see you mentioned the power steering pump forgive my ignorance but do I even have one considering its electric steering?

[Ascotgrun]

How do you adjust the tension on the belt?.

[///d]

Originally Posted by G05V8

Thanks for the reply! I see you mentioned the power steering pump forgive my ignorance but do I even have one considering its electric steering?

Ah good point. Depending on options some F15 have hydraulic steering. Active Steering and DHP options will come with it.

[///d]

Originally Posted by Ascotgrun

How do you adjust the tension on the belt?.

The N55 uses an auto-tension pulley, meaning it's spring driven and we can't "adjust" it, but you can check belt alignment and adjust as needed. If you feel the tension is out of spec than you may need to replace the tensioner.

[scotty339]

Originally Posted by G05V8

Hello, ever since it started getting colder I noticed when its 35 degrees or less my wifes F15 N55 driving from a cold start has a whining noise which fluctuates with RPM but tends to go away once the car is warm. I've had my transmission pan/fluid replaced a few months ago as well my serpentine belt along with idler pulley so I can pretty much rule out 2 common possible issues. Anyone else who reside in colder climates have this as well?

Did you replace the idler pulley OR the belt tensioner? They are different.

[G05V8]

Originally Posted by scotty339

Did you replace the idler pulley OR the belt tensioner? They are different.

Checked my invoice and it seems both have been replaced #11288604266 and #11288673720. Started to get a whirring howling noise anywhere from 20-60mph doesn't seem to be tire related as they have only about 3k miles on them (Conti DWS). Although my warranty expired about a month ago did make an appointment at the dealer next week hopefully it's nothing serious.

[Ascotgrun]

Is it an X drive?. Could be transfer case/differential issue. Wheel bearings are also a possibility. Just because tires are newish doesn't mean they were balanced properly or don't have a manufacturing defect from new.