Land Rover Repair: DII wont start, crank case, senser

Question
Hey John... where to start?? I have a 2000 disco 4.0, recently i went to leave work and tried to turn on my vehicle and all i recieved was the engine turning, but no fire. I tried periodically for 2 hours, finally it started. I went out later that day after turning off and starting 2 other times that day. Once again upon trying to leave, all i recieved was crank and no start. I then had it towed to LR Jaguar mechanic, once off the tow truck it started. I decided to leave it there so as to get some diagnoses. Well... 3 weeks and close to $1500.00 later, surprise it still wont start. Whats going on?? A senser in the crank case was changed, causing no solution. An old senser was put in, and now it starts, but then later in the day it just wont. I dont know if you can help me but some advice would be great seeing i keep spending money on new parts that dont fix anything. Thanks in advance for your help.  

Answer
Hey Grayson,

how's it crank'in?  :)

sorry...

Do you know if your DII is in passive mode?  I've been reading that LR has noted an increase in Disco II's slipping into a security passive mode and thus not capable of starting.   

Here's a quote from a reputable source (Chris St-Louis on discoweb.org):

VEHICLE MAY NOT CRANK AFTER BEING UNLOCKED

The customer may complain that occasionally the vehicle will not crank. This may be because the Non-NAS Passive Immobilization feature has been accidentally turned on in production or during repair operations.

If Passive Immobilization is enabled, the vehicle will immobilize itself if the ignition key is not turned to position "II" or the engine is not started within 30 seconds of unlocking the vehicle. With the ignition key in position "II", the vehicle will show that it is in the immobilized state by illuminating the alarm LED continuously. The engine will not crank if the ignition key is turned in an attempt to start the engine.

RESOLUTION:

REPLACE BCU WITH NEW OR RE-PROGRAMMED UNIT

So, could this be the case for you?

Typical causes of hard to start engines are:

inadequate fuel supply (fuel filter fouled, fuel pump failure, injector failure);

ignition failure (not enough spark, arcing wires, crack in coilpack, carbon buildup on plugs);

sticking exhaust valves (known problem with Disco II's);

hot engines (not your problem; fuel overheats and air can form);

air or vacuum leaks;

low oil pressures;

low power (battery weak, alternator failure, spark plug wires arcing);

ignition timing is off;


I hope this helps.

JohnMc