MP4.2+6.0

SSP says Hitachi was the OES for HPFP. Not common for SSP's to say stuff like that, but I noticed it.

Low cost next could be a combo of Techron in the gas for the injectors and Seafoam sprayed down the intake (past any sensors)--in case issue is either of those. Seafoam not perfect, but it is a DIY variant of some of the chemical based approaches like dealers may use. Frowned upon by some purists (who may mention outboards...), but has worked for me on some known direct injection foulers. Hot V makes intake side the very difficult side of head to actually service otherwise.

PaulW

At this point, you should do a compression and leakdown test. It will tell you a lot that the computer can't tell you.

SFD732

that is my next thing

2turbos4rings

Scope the valves next time you have the spark plugs off and check for carbon

Frag

Is the car burning excessive amounts of oil?

SFD732

negative

jattsta

sounds like a pcv issue. not normal to kill a row spark plugs or coil packs in one hit.