Whinging Fuel Tank

[mycroft]

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 .

[gordonsalive]

don't get the whinging, but does usually vacuum when I come to fill her up.

[mycroft]

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.

[shep1001]

There is a breather on the tank so maybe its kinked or blocked?

[konrad.holl]

I'm having this for several years now - might be the pipe to the carbon canister that's blocked. I leave the tank open just a fraction - no problems since. Otherwise, when the pressure gets too high, there's fuel smell in the cabin.

[Pursyluv]

I've had this, it wasn't the carbon canister, but the valve at the top of the breather pipe that had lodged open (I think that is what I was told)

[shep1001]

Funny never heard mine do this until the other day, went out for a noon tonight and it did it again, then I realised what it was!