Sounds like the EGR is blocked, it's the system that recirculates oil vapur from the crank-case back into the engine. Look for pipes that are soft and connect into your air filter or intake piping, perhaps the manifold, trace these back and they will go to the side of the engine and/or oil-filler neck or cap. If you remove and clean these pipes and any 'pots' connected to them it may help. Especially if there are sensors near to or within any of the sensors. If that's no help it may be a sensor or fault that will need a code-reader to pinpoint easily, most garages have them and usualy charge £5-10.
SteveP
January 2008
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