Fuel Tank Hisses At Me!

[Lacko 0]

When i go to fill up and take off the fuel cap there seems to be a lot of pressure behind it and it makes a hissing noise and a massive stench of fuel then appears!

 

I am just wondering if you guys know why it pretty much blows off the fuel cap when taking it off?

 

Any help would be great!

 

Cheers

Tom

[JRL 14 1 Cars]

I have not had this before but have a look under the rear wheel arch below the cap and there is a venting hose/drainage hose by the main filler hose. im not sure if its related but see if its blocked.

[harryskid 193]

Unless you have got a snake in your tank, it could be a blocked vent!