When did he mean the pressure wasnt building - I assume he meant during cranking,if so then there could be a problem in monitoring it as live data displays tend to freeze or crash during cranking.Does the Hp side read correctley when its running ? If it does then that pretty much cuts the high pressure sensor out of the picture.That leaves you with the pressure regulator,which I cant think of a sensible way to test off the car,or the high pressure pump.If as you say it runs ok once started and there is no rising of fuel in the leak off pipes - my money is on the regulator.Despite what the rave cd says it can be changed without removing the starter etc.Subbing it with a new one is probably the safest bet.Bearing in mind that the Hp pump is lubed by the diesel,I think if it was so shot it couldnt provide a decent start quantity/pressure,then performance would be very poor too.Darrnw said:Am I right in thinking the regulator is basically a valve actuator?
The reason I am digging at this is that the LR bloke said that the pressure at the common rail wasn't building up, therefore if the regulator on the HP fuel pump is frigged the fuel would be diverted back to the fuel tank. I took the return hose off the LP and it was ****ing fuel back as SOON as the ignition was switched to position 2! So I reckon the regulator is frigged I am planning on taking it off this aft can someone tell me how to test the reg if I take it off the pump?