Petrol Cap

[dl56uk]

my car's red light came on for the fuel low, when I unscrewed the petrol cap there was a heavy hiss, I put 2 gallon in and it went right over the 1/4 tank mark. should this hiss occur ? and if not could the breather pipe be blocked ?

[UKSWF]

I know nothing but suspect it is just Atmospherics (Air pressure in general) it is pretty wild at present in the North of England

[Hopkirk]

Mine has always given a loud hiss on opening, since it was new.

Come to think of it I haven't heard it recently, though the car is now 11 years old.

[TWR]

There should be a Pin Prick vent in the cap, check kit.

[tonyav]

Probably vapour build up because the tank was low on fuel.

[johnk]

My Fiesta always does this when the tank is nearly empty