HELP NEEDED! 2005 relay 2.2 DW12UTED

[Tdowie]

Hoping someone can help. I’ve got a limp mode and reduced performance/struggling to start issue with my relay van. It’s a 2005 with the DW12UTED engine (101hp).

It’s a struggle to start it without easy start, once started it’ll happily idle for as long as you leave it. Sometimes it won’t rev past 2k, sometimes it’ll rev to 2k then die and sometimes you can rev it as much as you want. If you drive it once you get to any form of load or about 20mph it dies.

Fuel pressure when cranking is 12-15bar which is of course far far too small, when running it sits at 50ish bar.
Struggling to do proper diagnostics as we’ve had 4 machines plugged in to the OBD and none can read the vin or autodetect. You have to put it through as a 2.3 Fiat Ducati for it to give you any codes. The ECU info states the ECU date is 2005 although on the ECU itself it says 2017? The wiring going to the ECU plugs aren’t in loomtape which suggests to me someone’s been fault finding.

It’s had 4 new injectors and codes in, cam sensor, fuel pressure sensor on the rail, fuel pressure regulator on the hpfp, in tank fuel pump, cambelt done with timing being checked of course at the same time, brand new EGR valve and cooler and a brand new rad pack and it’s still got this issue. All this work was done before it entered my hands.

There’s fuel going to the engine the in tank pump works but it’s nowhere near enough pressure in the rail. I do believe it’s a fuel pressure related issue but I’m not sure how to figure out if it’s the high pressure pump or a wiring/ecu related issue. I’m a technician in a garage myself but this ones got me and a few others very confused.

Cheers

[PaulC5]

Have you checked if the fuel filter has recently been replaced ?

[StevieE]

By any chance could the regulator on the pump be a faulty or cheap brand or maybe even the wrong plug be put on the regulator? The 2.0hdi engine has 2 regulators on the pump and both plugs fit but it obviously sends wrong signals and causes running issues. I’ve had a headache sort of similar but found a broken wire going to regulator on pump and done the trick. Don’t know how many cigarettes I went through but eventually got it. All the best mate

[Tdowie]

It’s had multiple fuel filters. I’ll try swapping those fuel pump plugs tomorrow and see if it makes any difference. It’s 100 percent a fuel pressure issue, will not start without brake cleaner to help it there’s not enough pressure cranking and barely enough to keep it idling. It’s figuring out whether it’s an electrical or mechanical issue as the previous owner has lost a fortune throwing parts at it.

[howardaskew]

I think StevieE was on the right lines. If the regulator opens (or fails to close?) at the wrong pressure you may lose pressure. Assuming the Pressure sensor is correct. I would be looking to see if you are getting the correct voltage at the regulator. The other possibility is that your high pressure pump is faulty. I assume that you have checked for leaks on the pipework from the HP pump to the Common rail and then to the injectors. Even a tiny leak will collapse pressure. It's worth checking the Low Pressure too. If you have a leak that allows air into the system this could also lose pressure. Check the low pressure piping too.