RRC 200tdi fuel tank hissing

Guys

My rangie diesel is off the road at the moment while I try and sort out a misfire.

The other day - like a complete knob - I was messing around with the handle on the lift pump.

Now it starts on 3 cylinders and runs rough and when I turn it off there is quite a loud hissing noise from the fuel tank and loads of pressure if I take the fuel cap off. So I've obviously created another problem.

Am I right in thinking I've got a blockage in the fuel tank??

Cheers

Will

Blocked breather tank breather?

Thanks blue beasty - where do I locate that and how do I unblock it??

Dont know on a RRC, some have a breather pipe off the fill pipe, some breathe through the cap