Volvo: 2002 volvos80 diesel, water condensation, throttle linkage

Question
car drives, but wont rev over 3,000 revs?

Answer
Shaun,
I am not familiar with the diesel engines as we do not use them in the United States. However the diesel needs air and fuel. Is the air filter or tube blocked or have a crack (split) in it? Have the fuel filters been changed? Is there a bleed on the bottom of the filter, maybe too much water (condensation) in the fuel? Is the throttle linkage stuck and not able to go wide open?