[rqjoe]

I have a puzzler for ya'all. My wife parks her Forester in the garage and at random times I walk by it and hear a buzzing/humming from under the car between the rear wheels. I am pretty sure it has to be the fuel pump running. But why? It'll just start doing it at any old random time for several minutes at a time. No key in car. Car cold. Car hot. I never hear the WRX doing this, just the Forester. 2015. 0 problems or other issues. Any ideas why it does this? Thanks.

 

[SD_GR]

First, make sure it's the pump. If it's the pump making noise, then the same noise should be apparent when the pump is definitely on -- since you may not hear it with the motor running, turn the key to the ON position and listen.

I suspect evap and/or other emissions stuff going on.

I should add I have a car that does something very similar, but it's only a 1991 model so I've not had a chance to look into it yet (read: I'm not worried... at all... it's been decades...).

 

[JaySin]

It's the evap system. My '16 WRX does it occasionally. I thought I had electrical problems in my garage until I figured out what it was. Lol
It's normal.
Edit:
http://www.subaruforester.org/vbull...hread-215930/#/topics/215930?page=1&_k=umt448

Sent from my iPhone using Tapatalk

 

[Firefighterjake]

My wife's 2015 Legacy does this as well on occasion.

 

[rqjoe]

Thanks all. Kinda figured it was normal, but wasn't 100% "sure" what it was. Also never would have thought evap. Does that mean it would be an air pump maintaining a pad pressure in the fuel tank? I am surprised I don't hear it in the wrx. Yeah sd-gr, I also probably would have never actually done anything about it either since car runs fine. Just one of those things that makes me go "hmmm?" Thanks all.

 

[rqjoe]

Oops JaySin, just read your link and see the leak check thing. That explains it.