Long time since I posted here but the forum has been a great source of information for a few faults in the year Ive had this car.
So following oil filter air filter service the beast has been out of action. First start after the oil change was fine. Started it up to move it off the ramps all fine.Switch it off and let it settle so oil level can be checked topped up bit over 1/2 litre to "max".
Start it again....no start. Cranks but fails to actually start up. Wait a minute, Try again it starts and idles at 500RPM no throttle response and runs like my old RV8 on 3 cylinders.
Realised battery is pretty much goosed.
Put on charge and once the earth terminal on the battery was tightened properly it started and idles properly. (New battery needed AGM I think is better but this current one isn't AGM)
Now it throws this restricted performance code P0088-22 when the engine RPM is increased whilst standing stationary.
I believe its associated to the pressure sensor AND the regulator. Weird timing after the service but these things happen I guess.
My question is how to pin point which one? So from my carsoft scanner I can see the pressures. "Desired fuel pressure" and "Sensor pressure" match right up to tripping into Restricted performance at around 2000RPM when the desired pressure stays high but the actual pressure drops off (because it limits the power output) I think that would be expected.
I have both on the way. Which one first or change both anyway?
I checked the loom part which is subject to fail but it looks fine. Meters out without any issue.
Any words of wisdom from the gurus?

Basic check first and I am sure you have, but is the fuel pressure sensor on the LH rail connected and undamaged? 2012 Vogue TDV8 in Aintree green over sand

From the manual for that code:

Low level fuel condition
Fuel gauge sender unit sticking
Fuel rail pressure sensor signal circuit short to power
Fuel rail pressure sensor internal failure 2012 Vogue TDV8 in Aintree green over sand

toby1 wrote:

Basic check first and I am sure you have, but is the fuel pressure sensor on the LH rail connected and undamaged?

Fuel pressure sender fault is favourite
Fuel pressure short to power..the voltage signal on the code reader suggests its not shorted but it could be inside the sensor itself.
The fuel gauge and fuel level match..3/4 tank.