My fuel tank whines sometimes , today in the hot weather after a long run I took the filler cap off and it stopped , there was a big suck of air like the tank was under vacuum. Is there a vent or breather pipe that is likely to have blocked . Or does everybody's car do this .
I used to get a bit of vacuum taking the cap off to fill but recently can here it trying to suck air in when I turn off the engine. I am sure I read somewhere but possibly not on here that a tank had deformed due to vacuum . Does everybody get this or is it a problem.
