What's causing this engine fault on a 2002 Land Rover Freelander?

Any ideas please? I have a 2002 Freelander TD4 with an intermittent fuel failure. It was travelling happily then suffered a loss of power with an eventual standstill. It will start again after about one hour. Work already undertaken: new ECU main engine, fuel rail pressure sensor, mechanical fuel pump, and camshaft position sensor. The vehicle has been sent to a Land Rover diagnostic centre - nothing - then back to a local garage - still not working. I have assured the owner that you will come back with the solution. Many thanks.

Asked on 2 November 2012 by AA, via e-mail

Answered by Honest John
Sorry, I don't answer questions of this nature unless I have come across the particular problem and know the answer. You need to use: www.honestjohn.co.uk/askhj/ from which it can be referred to our resident mechanic, Alan Ross.
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