Had the same thing, was have a little play up and down when got the funny tapping sound, spoke to dave & nick at PF and they thought it was a lifter, toldthem this was a car that manages to fix itself tried a bit later still the same thing, tried about 30mins later running sweet as a nut

Still think I need some anti pump lifters for it though

hope it's nothing too serious.

Did you not go in the end Gus