Engine miss

[SquareOne]

(02-08-2023 )Gapvalley Wrote:  ... High pressure fuel pump makes a lot of noise when it ramping pressure not sure if this is normal or not.

Has anyone looked inside that HP pump? Does the engine stumble any when going through the pressure test or is it smooth?

When a check valve in the head of my HP pump failed, aside from the small leakage out of one of the Torx style plugs at the top, it would stumble the engine while building pressure. I didn't finish the test to see how much it would bleed down since I knew the head was already compromised. The valve is a non-serviceable item, therefore the head needed replacement.