OK. Appmoore.
I had only just got my TD5 which had been ok until I put it up a big ramp - maybe co-incidence, but...........
I will save a lot of typing and cut the story short. I spent almost 4 months going through all the electrics. As I was convinced the problem was an intermittent electrical fault or possibly the immobiliser. When all that failed to solve my problem, I turned to the fuel system and replaced everything important from the tank end to the injector seals.
Problems I found on the way were.
1. Serious oil contamination in the ECU under the driver seat - Temporary solution was to clean out the plug - repeatedly until I could get time to fit a new (genuine LR) injector harness and repeatedly flushing out of the red plug on the ECU until no more oil appeared.
2. Replaced faulty MAF sensor - Hawkeye was showing some funny readings.
3. Cleaned MAP sensor - was in a hell of a state with carbon and crap.
4. Fitted EGR bypass - cause of hellish state of MAP sensor.
5. Fitted new CKP sensor - also lots of oil in connector.
6. Replaced brittle wires for connecting plug to CKP sensor which also had some insulation missing - this happens due to the heat from the engine.
None of the above cured my problem, but they did make a big difference to the engine when she was running.
Then, on the fuel system, I did:
1. Fitted a new fuel pressure regulator - no reason to suspect old one, but was gonna do it anyway.
2. Fitted new injector seals and o-rings - easy enough to do, but smear a little grease on the o-rings to prevent damage when re-fitting.
3. Fitted new fuel pump - no reason to suspect old one, but was gonna do it anyway and when I dropped the fuel tank and whipped out the fuel pump I found the filters in the pump were clogged with crap. While the tank was out, I also cut a large hole in the rear floor for easy access to the pump for future use, the hole will have an 8 inch boat hatch fitted as a cover. Once I got the tank off, I found there was a fair bit of gunge loose in the bottom of my tank and I came to the conclusion that the problem was caused by the loose stuff eventually getting caught up by the filter and causing fuel starvation. So my tank got a thorough cleaning out and a new fuel pump. The old pump is soon to be stripped down and cleaned to be kept as a spare, as is the fuel pressure regulator.
I would advise your first check to be for oil in the ECU red plug. This is a very common problem with TD5's. If you find it full of oil, clean it out with some sort of aerosol (most people say brake cleaner, but I used a de-greasing spray 'coz I can liberate the odd one or two from work.) Also, in the compartment where the ECU is, I found a couple of blue header connectors (blue plastic things with lots of wires going in) and mine were also full of oil. I'd clean them out too if your landy has them (mine is a defender.)
Next, check the CKP sensor for oil in the connectors, the signal from the CKP to the ECU is a very small one and it is easy for it to go astray, your engine will not start if it doesn't get a CKP signal - a handy immobiliser idea. If your wires are brittle, be careful when handling them, one of mine broke off just at the back of the plug when I'd fitted the new CKP sensor and I didn't notice it until I was about to re-fit the original CKP sensor. As an emergency repair, I cut back some of the plastic from the plug until I had just enough wire to solder on a new bit, this I wrapped in kitchen tinfoil, as the CKP sensor lead is screened to stop interference. Later, I noticed that the plug for the bonnet light switch (not connected on my defender) is the exact same as the plug for the CKP sensor so I chopped it off and used it to replace the damaged CKP sensor plug.
If oil contamination is your problem, these two things should get your engine started again.
If it's fuel related, I'd check the pump's built-in filters first to make sure they are clear. Drop your tank, but be careful with the fuel lines, I broke the little plastic nozzle on the end of one of mine because the tank slipped as I was trying to get them off, once you know how to remove the pipes, they are easy to take off. A black nozzle in the end of the fuel line slides into a clip on the pump and to release the clips you just squeeze the sides of the coloured bits to release the nozzle. Clean all the crap away from the top of the pump and unscrew the big metal ring holding it in the tank, there is a special tool for this, but I just tapped it gently with a big screwdriver and a hammer. The pump will spring up a few inches once the ring is unscrewed. When re-fitting, put the rubber seal in the tank first, then position the pump correctly (there is a slot in the tank for the sticky-out tab on the pump to go into.) It's a little fiddly, but I used a hammer handle to hold the pump down against the spring and got my helper to screw the ring back into place. Then re-fit the tank etc.
As for the fuel regulator, I replaced mine as I had no way of checking the fuel pressure at the time. I've never heard anyone say they are a problem, apart from leaking fuel which is apparently quite obvious if they do it, which mine didn't, but I had convinced myself that it was possible for the regulator to stay closed until the pressure was up and then to open to maintain the proper pressure, but maybe it was sticking open similar to a thermostat in your radiator. So for peace of mind I was happy to replace it. I intend to install a fuel pressure gauge once I get around to it, I've bought all the gubbins for this, I just need to put it all together. The same applies to my injector seals, I had no reason to suspect them, but I wanted to get this problem solved once and for all so I went through the entire fuel system in one go.
To bleed the fuel system after opening it up, switch ignition on and pump the accelerator 6 times. This should put your fuel pump into purge mode. It will operate for about 1½ minutes then stop for about 30 seconds, then it will re-start and run for 1½ minutes again. It will go through this cycle about 5 times then it will stop. You will hear your pump making quite a lot of noise as it purges the air from the system. I personally would recommend repeating the purge routine FOR AT LEAST 15 MINUTES. Or until your hear the pump has settled down to a nice quiet purr. When I did mine, I refused to try to start the engine until I heard absolutely no more of the "squealing" sound the pump will make as it purges the air - it tool about half an hour of purging before I was satisfied.
I must add, that everything I did, up until the fuel pump, did improve my engine, but none cured my problem until I'd done the pump. Since then, she has been running like a train and I love her to bits.
I hope some of this helps.
Where about in the world are you?
I could maybe offer assistance if close by.
Ron.
