Why is my Renault Laguna intermittently losing power?

I have a petrol 2005 Renault Laguna 2.0, the engine runs like a dream but sometimes when you are driving along there will huge loss of power for a few miles meaning that I have to drop it down to lower gears, then the engine will then just start running normal again for a few days. No engine management warnings lights come on and it has been computer checked, but that says there is nothing wrong. Can you help?
It would appear that the engine is going into "limp mode", but only intermittently. Therefore trying to identify the fault is going to be very difficult. With no warning lights and no faults shown via diagnostic it is not possible at this stage to identify. Would suggest that you check the fuel filter (last time it was changed?) and also the fuel pressure sensor.
Answered by Alan Ross on

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