So had my car serviced at my dealership in preparation for my big trip down south. Had brakes done, and basic service. Got my car back, thought i'd open her up and WHAM... code 29DC - Cylinder Injection Cutoff everytime i do a WOT. I check the forums and all basically say the same thing... HPFP.
This would be my fifth if it was the case. I told the dealer this so instead of the usual 'replace the hpfp' they did some investigating. They found some carbon buildup so do a full clean and tested the hpfp which held pressure as required. Gave me the car back and i've been running it for 2 days and NO ISSUES AT ALL. No more code and the car runs like a champ!