p38 diesel injection problem

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Idlewild

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I hope someone out there can help with this. My p38 diesel has been 100% reliable for the year I've had it. Until yesterday! It ran fine in the morning and then would not start 2 hours later. AA man was helpful but could not solve problem. These are the facts. There is no high pressure fuel to the injectors. I have removed high pressure pipe and cranked engine, no fuel. I have rigged temporary tank to ensure fuel is reaching the injector pump. There is 12v present on the stop solenoid when key is on. Glowplugs are working.
I think that this may be ECU problem but am not getting "check engine" light.
Any ideas
 
Hello, When you turn the IGN on are you getting the 'check engine' warning light, light up? You may have an alarm problem.
 
The light comes on when the key is turned and then goes out a few seconds later. An alarm problem had occurred to me but I thought the immobiliser stopped the starter circuit. Engine is cranking over normally. The dash display has shown "alarm fault" ever since I bought the car so that's not much help!
 
Hello.

When you turn the ign on my check engine light stays on until you start it. If you unlock and dont start within 30 secs then the check engine light goes out wont let you start.
I had a problem on my P38a 4.6 HSE that would just turn over and not fire, the check engine didnt light up ever, in the end the BECM was set to the wrong engine for some reason.
Never had a diesil before but there should be a electric lift pump in the fuel tank, are you getting power to this?
 
Hi
It's different on the diesel. After turning on the ignition you have to wait for a few seconds for the glow plug light and engine check light to go out before turning the key to start. This is all happening normally. I've tried provoking the system by disconnecting the diesel pump etc. This gives the result I would expect, that is the engine light staying on continuously. I also deliberately triggered the alarm, which reset as normal on the button.
Next thing I'm going to check is the stop solenoid on the injection pump as these fail to the "off" position as a safety measure.
Thanks for the help so far
 
hello @ all, I am new here with my P38 dse.

-worth to check the inertia switch, which cuts off the fuelling
-diesel P38 sometimes lose the synchronization between engine ecu and becm.
it has to be relearned to the becm using a diagnostic computer. I had this issue without any reason once.
the engine would crank and doesn't start, with no error messages on display.
-a weak battery causes a non starting issue on a diesel as well,
starter drains most of the power and the stop solenoid has not enough to open.
you could try a jump start and see.

cheers, korkut
 
Thanks for that. I've given up trying to sort it myself as i was going round in circles. BECM and ECU sent off for testing so will post result of that when I get it.
Mike
 
Hi, Just had to renew crank in mine and now i have the same problem...
Turn's over but no fuel to FIP..even removed the stop solenoid from FIP and still no fuel come out of the hole left.....
So let me know how you get on :confused:
 
The thing I can't get my head around is how the immobiliser shuts off the fuel supply. I assume it doesn't just enable the stop valve as that would be too easy for a thief to bypass. I wonder if it forces the ECU to send a "zero fuel" signal to the FIP. (same as when in overrun mode). Having studied RAVE for a few days it seems to not tell you how the immobiliser works. For obvious reasons, I suppose.
Anyway, I too removed the stop solenoid with the same result. The AA man who came originally suggested the Crank position sensor, but that seems to be giving an output, and I believe the engine should run in "limp home" mode without it anyway.
Still scratching my head!:mad:
 
If the solenoid is out and there is no fuel and you are certain anyway that it is not reaching the injectors, I suspect it may be mechanical, even as simple as a sheared woodruff key or snapped shaft inside the pump.

Although simple may not mean cheap....
 
I'd thought of that as well, as apparently the shaft does shear sometimes. Is there any way of checking whether the pump is turning with the engine without taking it off?
 
immob shuts all fuel outputs from pump you will still have 12v at solenoid but it wont pump anything, had a similar problem after i changed my engine but mine was blowing a fuse no24? by battery, it supplies engine ecu,turned out that the fusebox was ****e another £100 down the pan problem cured,the crank sensor wont stop it from running all it does is run at about 2500rpm tickover and the tacho wont work
 
"Eightinavee" wins the virtual bonus prize! Had my local independent LR specialist have a look with Autologic and that's what he found. Security relearn done and car as good as new. Well, nearly. It has done 130k after all!
Thanks to all for your help
Mike
 
Hi all, Can anybody please be honest with me and tell me what MPG you are getting from you P38 6 pot diesels, mines an auto and will never return more than 22 mpg and am considering spending money on pump/injectors and timing? with the cost of diesel I am relutantly not using it as much as id like,
 
That's probably about right. Mine's a manual and does about 23 round town, 30 on the motorway at 70mph and about 20-22 towing a caravan. Pumps and injectors come expensive and you'd have to think about how long it would take to get back the hundreds you would spend at an extra 1 or 2 mpg. These vehicles are never going to be economical, so like you I use mine a bit less and get the motorbike out a bit more
 
My P38 had an engine change by previous owner. Ican get her to start by direct feed to relay 12 but she starts and revs and then dies, almost like it only gets enough fuel to start and dies. My in tank fuel pump was not working and glow plugs not working from key. Light goes out but no power to glowplugs. Could it be the immobiliser or ecu issue. Going to check pump timing but the pump was not removed on engine change
 
I'd start with what doesn't work, like the in-tank punp.

The immobiliser should stop all fuel getting past the FIP so I wouldn't expect it to fire at all. If it does, even for a short time, then fuel must have got through somehow. Typically the diesel turns over but doesn't fire when it loses sync.
 
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