This vehicle was bought from the local auction with this fault so no history. The customer has fitted injectors,fuel filter and fuel pump, blown out the lines between the tank and filter.
The vehicle will start every time but not always run smoothly, no smoke or diesel knock. The rail pressure is 290 to 310 bars at idle and will rise to between 700 and 900 when accelerator is pressed. I have run the vehicle off an independant fuel supply but the symtom is still there. I've scoped the inlet metering valve and I see the command for more fuel (sometimes) when the pedal is pressed. Sometimes the signal does not change and this coincides with the stalling. If I graph live data (rail pressure) and scope (inlet metering valve PWM signal)at the same time I can see the falling rail pressure and the no change in the PWM signal to the inlet metering valve.
I think I'm in the right area but I can't think what can be commanding the shut off of fuel.

Any thoughts and input would be appreciated.