Disco 3 no acceleration?

My 06 plate disco 3 lost acceleration on Thursday, struggles to pick up speed in 1st gear till the tirbo kicks in. On the motorway I need to drop down to 3rd or 4th to get anywhere near 70 mph. What I have noticed is the engine is a lot quieter since this happened, no typical 'diesel' clicking/rattling sound on acceleration. The fuel consumtion readout has not move from 26.7 MPG since and I'm wondering if this could be a software problem, fuel problem, clutch problem or what, any ideas? It's only done 50,000 mls.

it will doubtless be one of the two egr valves not working, are you able to plug it in to a diagnostics.

Spot on, dealer said I need both egr valves replaced, it's being done today, should have the car back tomorrow. They gave me a brand new Freelander 2 GS till mine's is ready, quite a nice smooth car although when you get used to the space inside the disco the Freelander feels, well, ordinary, but I would consider one because of the fuel consumption.