My 2001 LF has been parked up under cover for 2 months, now it won’t start. Batteries good, turning over fine, but no attempt to fire. can pump the primer 3 - 4 times and build up resistance in plunger. Both fuel filters were replaced when I replaced fuel tank in October. it was running fine after this change. What should I check next?
agroman:
My 2001 LF has been parked up under cover for 2 months, now it won’t start. Batteries good, turning over fine, but no attempt to fire. can pump the primer 3 - 4 times and build up resistance in plunger. Both fuel filters were replaced when I replaced fuel tank in October. it was running fine after this change. What should I check next?
I’d go for wiring looms next - rats quite like to tuck into them.
Anywhere electrical I should be looking 1st? Possibly immobiliser issue? I have plugged in my Delphi diagnostics, but that has limited ability with immobiliser. Key chip looks fine. I have been doing welding on cab to repair corrosion and yes I did unplug ECU plugs, is there anything else I could of upset? Doubt if it is rodents as I have been working on vehicle regularly and yard is well baited! Wanted to eliminate any electrical gremlins before pulling the fuel system apart.
" it was running fine after this"
Is that: " It performed normally on the road and started normally a few days later" or "it idled OK for two or three minutes and revved up a couple of times after I had finished work on it " ?
It drove ok for a week and was then laid up. Come to think of it after it was left for a few days, it took a bit of cranking to start which is unusual. Wondering if I am getting a blockage or air lock somewhere in fuel system. Cannot see any visual signs of leak or bad pipes / joints and I have had it all apart once. Surprised if it is air that after priming it is not even trying to fire, so assume there is no diesel from injectors. So is there no fuel getting through, hence I need to check fuel rail pressure if possible or is it electrical which is stopping injectors opening.
Possible causes of this could be something like Immobiliser, crank sensor …?
agroman:
Anywhere electrical I should be looking 1st? Possibly immobiliser issue? I have plugged in my Delphi diagnostics, but that has limited ability with immobiliser. Key chip looks fine. I have been doing welding on cab to repair corrosion and yes I did unplug ECU plugs, is there anything else I could of upset? Doubt if it is rodents as I have been working on vehicle regularly and yard is well baited! Wanted to eliminate any electrical gremlins before pulling the fuel system apart.
TBH you’ve sort of answered your own question from the symptoms you’ve posted if it’s not making and slight splutter to start after a load of cranking, and was working before laid up, it sounds like the electrics are stopping it so as you’ve mentioned stuff like immobiliser key and trying a spare key is where to start. If it’s something else then something will most likely have happened to the electrics like water shorting something or something severed. I would worry the welding has fried or melted presume you disconnected battery also.
Yes batteries isolated all the time. Spent some time with my Delphi plugged in. I have come up with VIC codes:
27201-19 Engine running output, interruption or short circuit to ground. Permanent. The DAVIE manual shows "No CAN message received ’ Engine speed’.
24201-19 CAN message from ECU. Interruption or short circuit to ground. Permanent. Can’t find this in DAVIE manual
24205-19 CAN message from Tachograph. Interruption or short to ground. Intermittent.
Wondering from 1st code, if it is a crank sensor issue. Will remove and clean sensor and ring.
Do you any engine warnings on the DIP panel ■■?
Electrically wise ,are the batteries fully charged ? I can’t remember the exact voltage but if the drop below say 20volts when cranking the engine ecu will shut down as all the power goes to the starter
Does it have a mega fuse behind the battery box ? ,they are prone to rotting away
You say you had all the bulkhead plugs disconnected ,you have pushed them all in correctly ■■ Also the pins do suffer from corrosion which can cause issues
Does you Delphi read fuel pressure when starting
It should still start with the crank sensor down and it should give a warning on the DIP
Are you getting all your feeds and earths at the ECU■■?
Lastly is the small earth ■■■■■■■■ the ECU OK ■■?
It may well indeed be your VIC issue which is a Pending /Active fault ■■
Fuel wise things to check
Remove the feed pipe to the common rail and get someone to spin the engine over see if you are getting fuel.if not then strip the pre-filter head and check for debri ,you no doubt have a metal tank and they corrode internally very badly and choke the filter …
If you do have fuel at the common rail feed pipe ,remove the pipe from the prv on the rail and see if that is ok …ie no fuel should come out the rail…Then remove the leak of pipe from the rear of the head and spin it over there should be little to no fuel coming out
You can also unplug the main fuel pump,though it will activate a red warning ,it will default the pump to max fuel pressure
Hi Norbert thanks for your time and expertise, i really appreciate it. I’ll try and work through all you suggestions systematically… I can start by:
ENGINE WARNINGS ON DIP PANEL = air pressure low (obviously) and Alternator warning in orange. Also stop light on.
Batteries good, fully charged… I have had battery box off to derust. Replaced mega fuse holder and fuse at same time. All connections clean and tight. When I 1st got the truck it had really stuffed batteries, but would still start if there was enough charge to spin over at sensible speed.
Checked all bulkhead and Ecu plugs all look ok.
Unfortunately Delphi cannot communicate with fuel system without engine running not with ignition only.
Have cleaned and checked crank sensor and exciter ring anyway.
Is there info on voltage and earth cable location at ecu plug? To help with testing.
Where should the small earth strap be located? I cannot see a separate one, other than the braided wire connected to the block just below the ecu… This one look fine.
If it is a vic fault as per Delphi codes, what is my best action?
Fuel wise I am getting fuel when cranking from the main fuel rail feed pipe. Tank has been replaced and all lines / filters cleaned / replaced. You say remove the pipe from the prv on the rail. I assume this is the valve on the back of the rail. If I remove the pipe from this valve and crank I get fuel from the valve. Removed leak off pipe from back of head. Little to fuel here when cranking…
Forgot also tried cranking with plug removed from pressure valve on pump. Still no joy!
If I remove the pipe from this valve and crank I get fuel from the valve.
You should not get any fuel whatsoever from that valve on the end of the fuel rail…So as long as I read it correctly you have a faulty rail /PRV
OK
To clarify, there was a few drops of fuel from the valve when I removed the fuel pipe. When I cranked engine there was enough fuel to make the top of the head wet and for a few drops to run down the fuel pump and drip onto the ground.
Do I go for just the prv (I assume this is pressure regulator valve?) or should I change the whole rail? Should I go new or secondhand to save money?
Thanks
I have stripped down the PRV. Its very simple, can see nothing obviously wrong with it unless spring has become weak. Before I spend money on a replacement, a question about this valve. When cranking the engine, if the injectors are not triggered to open would the fuel pressure become high enough in the rail to make this valve work and release pressure. This is what appears to be happening.
Your vehicle is a euro 3 going by its age …I have never known them build up enough pressure for it to leak when cranking…The only other thing electrically that I can think of is if the CAN is down…You have 2 twisted wires yellow and blue 3700E 3701E at the bulkhead you should get 60 ohms, with it disconnected you should get 120 ohms at the plug and socket and your looking at 2.5 to 3.5 volts .Though if you have fuel coming out the PRV when cranking that is not correct
How much fuel you got in the tank
sheep1:
How much fuel you got in the tank
30Litres in 110 litre tank. I know exactly because I drained old fuel and replaced with new, I found 6 - 5litre fuel cans!
Ordered a new PRV.
In the mean time I have 'modified the old one by putting some washers behind the spring thereby increasing the pressure on the valve. Now when cranking there is no fuel coming from the valve, but still no firing 
I have checked can bus at brown socket on bulkhead. I have got 64ohms across the 2 cables and 2.4v from each cable when ignition on.
Where to next?
Forgot to say
with brown plug removed, there is 130ohms on the engine side and 120 ohms on the cab side.
Coming back to think about immobiliser?
Key chip looks fine, unfortunately I haven’t got a spare key to try. The tel tale red led in the roof panel is blinking as normal, not sure if this should change if ignition is turned on or key in? Is there any way of testing or bypassing immobilser? I can see immobiliser with Delphi but have no ability to check key coding etc.
agroman:
sheep1:
How much fuel you got in the tank30Litres in 110 litre tank. I know exactly because I drained old fuel and replaced with new, I found 6 - 5litre fuel cans!
I have changed a couple of tanks on daf lf45
They Never liked to start with less than a quarter of a tank just won’t fire up
Diesel in tank isn’t high enough
Working through elec system. I have power at ECU plug through 4 red feed wires. But have orange alternator warning on dip and Delphi cannot communicate with ECU. Thinking it was ECU problem, I sent it of to Alliance for testing. Came back with a ‘micro fault’ which they cannot fix. Quoted 1.8K to fix by sending to Bosch - no thanks! So had it back. In the meantime borrowed another ECU from a mechanic. Plugged in but could not communicate. Then noticed the main lower plug into ecu. The clamping arm was closed against the body of the plug, however the locking slider was about 1/4 inch out from the body of the plug. managed to push the slider tight against the body and we then had communication. Swapped back to my original ECU and hey presto off we went! Not sure what the ‘micro fault’ is but the engine appears to be running ok!