I have a focus cmax 1.6 TDi and have two problems :-
When I fill with fuel, the fuel pump cuts out regularly unless I let the fuel in slowly.
Occasionally I have a problem that the engine stalls. When it does so, waiting a while then starting agains usually works fine and I can driver for months before it happens again. Doesn't seem related to when I refuel.

I'm considering taking the fuel tank off and swilling it out with fuel, to remove any residue which may be blocking pipes. Before I do that though I'd like to check the fuel tank breather hose is clear, how can I do that ?