Technical JTD no fuel pressure

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Technical JTD no fuel pressure

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Apr 21, 2018
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Hi,
Trying to get a 2000 reg JTD running that has been stood for years.

The in tank pump had packed up so I replaced this and it now runs for about 30 seconds every time the ignition is switched on, if you slacken the feed and return pipes to the high pressure engine pump at the the fuel filter there is plenty of fuel pressure, the key code light goes out and the preheat light comes on., flashes and goes off, the engine cranks over and the cambelt turns. I released one of the fuel gallery feeds to an injector but there is no fuel even with the engine cranking, I have checked all the fuses and cut off switch and all appear ok. Where should I be looking next? :bang::bang:
Is there a fuel cut off solenoid on the HP pump or is that just a pressure regulator?
Does anyone have a wiring diagram or system operation description?

Really want to put it back on the road but if it carries on like this its going to the crusher which would be a shame!
 
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The HP pump has a fuel pressure regulator (IMV = Inlet metering Valve, if this is stuck then no fuel will pass through the pump. If you take it off you must be very scrupulous about cleanliness as a few specs of dirt will block it and/or the pump/injectors.
They do fail (ask me how i know!) and it is not too expensive.
Some people say tap it a few times and try again, it may work!
 
Hi,
Thanks for sort of confirming what I already suspected, the fact that the fuel is getting to the pump narrows it down to either the pump or its controls. I tried tapping the valve a few times tonight but no improvement, the car is on ramps so i'll have a look from underneath and possibly take the valve off and test it. I used to be a mechanic but I gave up repairing cars for a living just as common rail came in so know the basic principles but never done any repairs other than filter changes - It must be the pump or valve - I believe there is a 12volt feed to the the valve and the ecu earths to actuate it, probably get the voltmeter out too.

Everything is so hard to get at on the back of the engine.
 
So, removed fuel valve from back of high pressure pump, theres a silver pin sticks out next to smaller green washer in the centre,this pin will rotate (or silver cap does) but not move in or out. Tried testing on battery but no clicks or movement... presume its seized and regulates fuel by moving in and out?
 
Have you hooked up a scan tool. (Multiecusan).. it’s free and you will be able to check the manifold pressure. If it’s not high enough the injectors won’t fire(you’ll see what the target pressure is on the scan tool, I think it’s 200 bar)
That’s where I’d start... you’ll also see if the pressure drops during the 30 second run causing it to stop.
 
I don't have any diagnostic equipment.

If you remove the FCV on the high pressure pump and switch the ignition there is plenty of fuel pressure into the HP pump, The original FCV valve appeared to be seized - its supposed to work like a solenoid but although there's a circuit through it nothing happens when you test it on a battery apart from spark as you connect. I got a second hand HP pump and swapped the fcv over but still only a trace of fuel at fuel rail so i've either got two faulty valves or a faulty HP pump! There's a 12volt feed from the ecu to the fcv and then the ecu is supposed to earth it to control the fuel flow.
I checked the supply voltage to the fuel pressure sensor and its 5 volts as it should be, disconnecting it also brought on the red engine fault light so all the electrics side would appear to be ok.
As it needs a new alternator, cambelt change and now possibly a HP pump as well as a brake pipe across the back of the bulkhead I think we will drop the engine out and swap if for a known runner, cheaper time and parts wise..
 
You said it will run for 30 second.. is this still the case?.. if there wasn’t enough pressure at the rail it wouldn’t run at all. Have you some easy start?.. maybe a lazy pressure sensor on the rail.
 
Sorry, badly worded! The pump in the tank runs for 30 seconds everytime ignition is switched on but the engine won't run at all, not even a splutter.. Was running ok when parked up but thats 6+ years ago - who knows what time could have done? Most of the electrics do seem to be working ok though.
 
Ok that adds up better then.. get some easy start I’d say, at least that will fire it into life and it may spin your pump up sufficiently to get your rail pressure where it should be.
Marty.
 
You seem like a man of knowledge! As its done 140,000 miles, needs an alternator, cambelt and possibly HP pump as well as a brake pipe easily done with engine out and the clutch used to be heavy from memory we are just going to put a known good engine and gearbox in, the question is - would you get the engine ecu off donor car or will this cause all kind of alarm and key code issues? I know your supposed to program the injector codes in but this is only micro fine tuning and it will run ok without.
 
I’m really not sure on which Ecu you should use, someone else will be along though,... what I do know though is luckily for you the injectors on that engine don’t need programming :)
 
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