Hi,
I have a 2006 Ford Focus 1.8TDCI which has a vibration when the engine reaches 1800rpm, but then stops after the engine passes 2000rpm. I can hear the vibration and feel it through the steering wheel.
It does not seem to be related to road speed at all - only to the engine speed.

I have not had the car for long and any help you could give would be appreciated.:)