Possible fuel cap issue?207 1.4 hdi

[bogdangy]

Hello again!I am struggling since last year to "cure" my 207 1.4 hdi that cuts out very often.I replaced many parts,sensors,fuel filter,egr,but no luck.Recently I noticed air in the fuel lines,especially when priming bulb,lot of air bubbles,also the bulb seems to be soft and would take a couple of seconds to return to its initial state and shape.Another guy with same issue thinks that there is a vacuum created in the fuel tank and the possible reason would be the fuel cap that apparently has a breather valve.I cant find detailed info about this issue on google but I heard only one similar case where the fuel cap was the issue of engine stalling/cut out,Ford Focus 1.6 tdci,which diagnose showed up an error code that I cant remember..