Range Rover P38, 1995, Manual Diesel - Range Rover P38 - Diesel not starting/running - Lukas Stapleton

Evening All,

I have the above vehicle as a project car and I am experiencing issues with starting and running the engine. It started with rough idling, loss of power then cutting out and refusing to start. It is a complicated tail and have posted on specialist forum but not really got a definitive guide on what to do next. These engines are a BMW M51 direct injection, 6 cylinder, timing chain with a fuel injection pump modulated off timing chain. Very complicated computer systems involved on these cars.

Below is what I have tried

1. In-tank pump changed (leaking due to corrosion), bled to injector pump. No start.

2. Fuel injection pump changed for a refurbed unit and bled. No start. Injectors bled also.

3. Timing is all correct along with fuel injection pump timed. No start.

4. Car computer and engine ECU are synchronised.

4. Engine starts on easy start but does not idle. Black smoke.

5. Compression test passed all within accepted values for 178,000 miles on clock.

6. Valves seem to be moving ok.

7. Range Rover diagnostic displayed no fault codes apart from invalid major engine fault which is not helpful.

Below is what I can think to check next:

1. Crank position sensor - ordered awaiting delivery

2. Injector 4 has a sensor built in and plugs into wiring loom, ordered awaiting delivery.

3. 3 of 6 glow plugs faulty, ordered awaiting delivery (albeit it wouldn't affect running when started?)

3. Leak back test on injectors.

I am struggling to think what else it could be and scratching my head as to what to try next.

If anyone can have a read see what I have missed or can try?

Thanks

Lukas

Range Rover P38, 1995, Manual Diesel - Range Rover P38 - Diesel not starting/running - Railroad.

A very complicated computer system you say. Well it's not as complicated as you like to think. Any diesel engine complicated or otherwise needs the following four things. If it has them all it will start and run.

1. A good supply of air

2. Good compression, around 18 or 20:1 ratio

3. Fuel injected at the right time in a high pressure spray

4. A clear and unrestricted exhaust.

If your engine doesn't run then one or more of these four things is the reason why.

Range Rover P38, 1995, Manual Diesel - Range Rover P38 - Diesel not starting/running - focussed

Have you checked the stop valve on the injection pump is working properly?

Is the terminal on the stop valve showing live with a test lamp when you are trying to start?

If it isn't, fuel won't get to the pump and the engine won't run.

Edited by focussed on 14/10/2019 at 22:14

Range Rover P38, 1995, Manual Diesel - Range Rover P38 - Diesel not starting/running - elekie&a/c doctor

This will be running a Bosch Edc electronic fly-by-wire diesel pump. There is no visible fuel shut off solenoid. Diagnostics on this system is very limited, unlike the later common rail systems. You say that the pump has been changed, but has it been married to the car electronic immobilser system.? Is there any fuel at the injector pipes?

Range Rover P38, 1995, Manual Diesel - Range Rover P38 - Diesel not starting/running - Railroad.

If this is an EDC system it will have a needle lift sensor on one injector. This MUST be fitted on the correct cylinder, which on a 4 cylinder engine is No.3. I think it's also No.3 on a 6 cylinder engine, but I'm not 100% sure of that so double check.

You say the engine will run on Easy Start but it produces black smoke. That's a sign of insufficient air. You can do a lot of damage to a diesel engine with this stuff so if you must use it give it only a tiny sniff. If you hear the engine knock you've given it too much. If it won't start with just a sniff then something is clearly wrong. Make sure the engine draws clean air and is not clawing back its exhaust gasses, on which it cannot run because there is very little oxygen. Do you see light colour smoke from the exhaust when you crank the engine? It you do you know fuel is being injected.

Are you 100% certain that the fuel pump is correctly timed? Even the smallest adjustment makes a big difference to the pump timing. Also are you sure air isn't getting into the fuel system around the fuel filter?

Forget fault codes. They mean very little and can easily lead you up the garden path. But a scantool is very useful for live data checks. Do you have an engine rpm signal when you crank it? Use a scantool to check this. If you do you know the crankshaft sensor is working. This is the only sensor that will prevent the engine from running if it's faulty. None of the others will. The good thing about live data is you see what the ECM sees.

Range Rover P38, 1995, Manual Diesel - Range Rover P38 - Diesel not starting/running - focussed

S'funny - every parts diagram has one for that pump - Bosch don't call it a stop valve or stop solenoid they call it an electrical switch. On the top of the rotor housing.

Range Rover P38, 1995, Manual Diesel - Range Rover P38 - Diesel not starting/running - Lukas Stapleton

Morning all,

Sorry for late reply been off sick and thanks for tips.

I changed the crank sensor as it was damaged, replaced faulty injector, it run but was hunting, grey smoke.

I suspect there is a lot of crap in the system and injection pump timing is out a bit, so got the tools and will try and time it up this weekend.