What's this whirring noise under the hood?

elvisimprsntr

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On my '25 1.5L (cold engine), when I unlock the and open the door, I hear a whirring noise at a constant pitch. It will slowly increase/decrease in pitch every ~60s and remain at a constant pitch. Even if I close the door and lock the vehicle it continues to run, but it does eventually stop after a few minutes.

The only thing I can think of is the low pressure fuel pump, maybe associated with a leaking fuel injector test? If it's the low pressure fuel pump, why would whirring noise come from under the hood when the low pressure electric fuel pump is in the tank? I thought I read the '25 high pressure pump is mechanically driven.

I read the other possibility is the coolant pump or headlight condensation fans.

UPDATE: I confirmed it's the headlight fans.


 
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Warped9

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If it's the sound I think you're talking about I hear it when I turn the car off, but only if I pay attention to it and only when I'm parked in the garage. Otherwise I don't hear it.
 

tommy

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On my '25 1.5L (cold engine), when I unlock the and open the door, I hear a whirring noise at a constant pitch. It will slowly increase/decrease in pitch every ~60s and remain at a constant pitch. Even if I close the door and lock the vehicle it continues to run, but it does eventually stop after a few minutes.

The only thing I can think of is the low pressure fuel pump, maybe associated with a leaking fuel injector test? If it's the low pressure fuel pump, why would whirring noise come from under the hood when the low pressure electric fuel pump is in the tank? I thought I read the '25 high pressure pump is mechanically driven.

I read the other possibility is the coolant pump or headlight condensation fans.

UPDATE: I confirmed it's the headlight fans.


On my '25 1.5L (cold engine), when I unlock the and open the door, I hear a whirring noise at a constant pitch. It will slowly increase/decrease in pitch every ~60s and remain at a constant pitch. Even if I close the door and lock the vehicle it continues to run, but it does eventually stop after a few minutes.

The only thing I can think of is the low pressure fuel pump, maybe associated with a leaking fuel injector test? If it's the low pressure fuel pump, why would whirring noise come from under the hood when the low pressure electric fuel pump is in the tank? I thought I read the '25 high pressure pump is mechanically driven.

I read the other possibility is the coolant pump or headlight condensation fans.

UPDATE: I confirmed it's the headlight fans.


My 2021 OB has always had a noise from the headlights even sometimes when in the garage and it's been parked for several hours, then it stops, that said I do live in South Florida., maybe the 90-degree garage temperature sets it off?
 
 







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