question about fuel pump

I have a 2010 Tacoma reg. cab, 4 cylinder, 5 speed. Today, a good hour after I parked it in the garage I could hear a humming noise from the left rear. It sounded like the fuel pump was running. I turned the key on and off again and it stopped. Any ideas out there? Thanks, Jeff

 

next time you hear it,loosen the gas cap and see if it goes away.it maybe venting the pressure from the fuel tank.

 

I've had this happen to me on my 2011. Similar senario, parked in the garage on a warm day. I'm pretty sure it was the fuel pump venting the tank. I loosened the gas cap and a rush of air came out. The pump stopped immediately. I've wanted to look it up on a schematic to verify, just haven't taken the time.

 

That is the EVAP system working, not the fuel pump. It tests the vaccuum of the fuel system, checking for leaks.

 

Thanks for the great tips!
Silvert