Hey, this is my first post

I just bought a 94 1.3 lx fiesta with 50k on it, it runs and idles perfectly. But on longer runs it cuts out randomly when slowing down to a junction, (car just won't rev, like its ran outa petrol. then dies) it starts up then cuts out again, then starts and runs well again

Have just changed the plugs,fuel filter and air filter, any ideas what it could be?

cheers baz