Your vehicle is a euro 3 going by its age …I have never known them build up enough pressure for it to leak when cranking…The only other thing electrically that I can think of is if the CAN is down…You have 2 twisted wires yellow and blue 3700E 3701E at the bulkhead you should get 60 ohms, with it disconnected you should get 120 ohms at the plug and socket and your looking at 2.5 to 3.5 volts .Though if you have fuel coming out the PRV when cranking that is not correct