Ds5 diesel hybrid 4 fuel issue

[Leejasp]

Car started drives fine until going up hill or over 50mph. When checking error codes it has thrown up the following.

P11AC has anybody got any ideas. Eml on and red message to stop wait 5 mins then off we go as long as we keep it under 50mph.

[GiveMeABreak]

Here you go:

Fault Code:	P11AC
Description of Fault:	Fuel flow regulator : Control current not plausible Description of the diagnostics: Difference of less than -300 mA detected for 5 secs in the control current of the position of the flow rate regulation valve of the high-pressure pump compared with its default opening with a high demanded flow rate. Conditions of activation of the diagnostics: Engine running over stabilised periods.
Conditions for Fault to clear:	Driving with a warm engine for 5 minutes with several stabilised periods under heavy load for 20 seconds
Downgrade Modes whilst Fault is active:	Request for Delayed Engine Stop Prohibition of the combustion mode that encourages regeneration Deactivation of the kick-down for automatic gearboxes Limitation of performance Deactivation of the request for regeneration of the particle filter from the diagnostic tool Switching on of the warning lamp and/or warning message: - Warning lamp MIL - "SERVICE" warning lamp - Warning lamp STOP
Symptoms:	Engine hesitating, cutting out Slightly higher fuel consumption Lack of power Fluid leak / Smells Absence of automatic stopping of the internal combustion engine Problem activating the power unit Forced driving in electric transmission only
Suspect Areas:	Gasoil filter Pressure sensor on the fuel high-pressure injection rail Electrical harnesses Low pressure diesel circuit Fuel high pressure pump Fuel high pressure common injection rail Fuel high pressure pipes