Yes same problem new high pressure pump ,but after pressure test, pressure fell away rapidly.removed hpsensor to find the sealer oring was kaput.so.will replace both pumps ,fit new. Orings to pressure sensor ect then see where we are.
Compression test first check reading ,2 put some oil into the suspect cylinder if reading is higher suspect piston rings if not suspect valves,all compresion test should be similar.
I have the same problem lads vst stripdown twice high pressure pump replaced low pressure pump on its way nightmare now third vst to come out again so a can check out this grommet
.