Oh great and wise HDI Gurus...

[Ruan]

Does it splutter when you put the usual combustibles down the intake?

For the record - I'm not saying it's NOT the HP pump - I'm simply saying it sounds absolutely typical of a LP pump...

As the old saying goes - if it looks like a duck, quacks like a duck, swims like a duck... Probably is one...

Are LP pumps a common failure point - yes.
Do LP pumps cause problems starting - yes.
Do LP pumps cause it to sometimes cut out under high load - yes.
Are LP pumps a cheap and easy item to replace - yes.

Are HP pumps a common failure point - no.
Do HP pumps cause starting problems - yes.
Do HP pumps cause cutting out under high load - yes - but not cause problems starting, then happily make 900+bar.
Are HP pumps a cheap and easy item to replace - no.