Was on here before requesting help for this problem, the symptoms are that the car starts first thing in morning but at some points during the day it will refuse to start, it will run for a few seconds and then cut out, there are no revs or power in the pedal so I just have to keep turning until it starts.
I was advised to change the o rings in the front pump, after a long wait this job has been completed but unfortunately was not successful.
So i am turning again to the forum for suggestions on how to rid the car of this problem any suggestions much appreciated.
Many thanks
John walker

a faulty camshaft sensor is often a cause for hard to start when engine is warm
but i think that's just 'starting' ..
if it runs then cuts out .. could be an injector at fault ..

or "could be" .. i.e. lots of 'could be' s to chase ..

see :
fault diagnosis:
https://www.landyzone.co.uk/land-rover/75-zt-td4-fault-diagnosis.203935/
(*1 .. the td4 uses a variable vane turbo .. 'n later models don't have the fuel tank lift pump )

try a forum search " td4 hard starting "
or " td4 hard starting when warm "
be loads of threads on that .. common issue with the td4
( never had the issue myself .. so no 1st hand experience )

probably the best advice .. as often given ..
is to get a diagnostic test done ..

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Had a similar issue with mine. It would generally start and run well. Randomly, after starting, it would not respond to the pedal, then stutter and die. It would then take about 15 seconds of cranking to start, with lots of farting and a cloud of white smoke.

I ruled out the HP O-ring as I’d rebuilt the pump a couple of years ago. Gave it a service including fuel filter, put it on the Pscan diagnostics - nothing. Rail sensor upgraded already. I did try some injector cleaner and running on decent fuel for a while, but it still played up now and again. I even cleaned up and dielectric greased the chassis earth points and connectors.

My guess would be a sticky injector leaking back and preventing starting intermittently. I did a leakback test, which showed no problem, but then the car wasn’t showing the fault at the time. Intermittent faults are the worst.

The problem seemed to go away by itself. I suggest:

Full service
Diagnostic check
Leakback test
Injector cleaner/decent fuel

When it does play up, try to note the exact conditions: Fuel type, weather, engine temp, etc. It might help guide you to the cause.