Driving into work this morning in the 159 jtdm and all of a sudden I'm hearing a horrible fast juddering/knocking noise when I bring my foot off the accelerator. The noise goes away when the engine is pulling and when the brakes are being applied but as soon as the car coasts in gear the noise starts up.
It is happening in all gears and is worse in the higher gears undoubtedly because of the speed. In the lower gears the juddering noise is slower but about the same noise level.
My first thought is driveshaft, any advice much appreciated.