ZT CDTi Check Engine Issue

[Bob the Boss]

Hi everyone. I'm hoping that someone will be able to help me with this issue that's been driving me mad for the past fortnight. I've got a 2004 ZT CDTi with 171k on the clock. For the past two weeks, whenever I use cruise control on my way to work and get to a certain point on the motorway with a slight downward gradient, the check engine light comes on. It then stays on for around a day, and goes out again, until I use cruise control again for a few miles. It only ever comes on when using cruise, as well. I've just changed the fuel filter to see if it made any difference, but the light just came on again just now when I took it for the same drive to test it out.
We cleared the fault code last week using TOAF, and that came up with a slightly low fuel pressure fault. I don't understand why the light is only coming on with cruise activated, though. Can anyone please offer me some advice on this? Many thanks in advance for your help.

[Lee T]

Try a battery reset. This trick has cured faults on many cars. Scandinavian reset also worth a punt, touch the DISCONNECTED neg and pos battery leads together for 30 seconds, then leave for 30mns before reconnecting.

Lee.

[macafee2]

There is an electrical plug at the top of the fuel filter, pull it out and shove it back in a few times. Seems to work on my 2 diesels.

macafee2

[Bob the Boss]

Hi Guys! Just trying all of your suggestions right now. I'll let you know how I get on!! Thanks to you all!

[Arctic]

Hi John.
Try what Ian has said remove the connector from the low pressure fuel filter pump, spray a little contact cleaner into the connector and the unit, plug and unplug a few times see if that cure sit.

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You could also do the turbo boost sensor.
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