2011 3.0 TDI - Intermittent starting, Gear selector issues

[Bobbybee]

Good evening folks, Having issues with my Q7 with the following

• When accelerating hard anything over 2500 rpm and Glow plug light flashes and car goes into limp mode P008701, once shut off and restarted all ok until next harder acceleration.
  • Replaced Fuel filter, Replaced Fuel rail pressure sensor, replaced Fuel pressure regulator, Replaced Main battery and coded to car. Injector #4 was grossly overfuelling, replaced injector and found copper washer and seals missing. Having done all of this I still have the same issue and less hair! I think the only thing now is the HPFP? Any Ideas???
• Car began playing up today intermittently not starting, Put booster pack on and eventually started, and was ok for a few starts then intermittent no start. This along with the new gear selector issues below.
•  Gear selector locked up numerous times in Park, cleared faults and always ok until I go back into Park then It locks up again. Been a brilliant car but now driving me nuts lol.
• ANY IDEAS OR ASSISTANCE GREATFULLY APPRECIATED ON ANY OR ALL OF THE ABOVE ISSUESTO GET MY SUPER SMOOTH Q7 BACK. COULD ANY OF THE ABOVE BE LINKED??      Cheers Bob

[Steve Q]

Has the battery been checked? 

Any fault codes for the gearbox? 

When was the gearbox last serviced?