Have a Vauxhall Movano towed in non runner fault codes P0089 pressure regulation sensor circuit 'overheating!' with other codes referring to the air mass p0108/110 though these have cleared and were probably a result of the rac lad pulling plugs off when testing as faults are cleared without return.
The symptoms are very difficult to start with pressure only 100-150 bar but eventually starts at about 350 bar will run if throttle held at 3000rpm pressure 550- 600 bar but if left to tick over fuel pressure diminishes eventually stalling when dropping below 150bar.When attempting to drive eng man light comes on at about 40 mph and vehicle stops but will restart after severe cranking and allowing to limp back to garage where on code reading the p0089 code is there with the strange statement of pressure regulation sensor circuit overheating.Have come across this code quite a lot primarily on nissan and had success with simply replacing the imv valve on the side of the pump and carrying out a fuel adaption, on this occasion a new unit has not cured the problem.Have done the normal leak off checks at idle and speed without any excess from any one injector.Provided separate supply to eliminate tank and filter to no avail,scoped injectors and imv valve all wave forms appear good with the duty cycle of the imv being 30% and the fuel temp reading approx 50- 60 degrees.My question is what is the cause and effect of the sensor saying it is overheating?Does it appear that the pump is making it work overtime ? though i don't see any over pressure from the pump according to the pressure sensor output which i am monitoring permanently throughout.I have also tested the pumps ability to provide max pressure by blanking off the imv valve which sort of eliminates the pump would you think.Any thoughts would be a help.Regards J