I have a Mazda 6 TS Diesel 140000 miles.
Its suffering a severe loss of power with loads of black smoke at high revs.
Seems to be a diesel knock in the engine at low idle speeds and intermittingly the revs wont climb above 3000 with foot flat to the floor.
My mechanic has checked turbo, cleaned EGR valve and done injector leak-down test, all the above is ok but the problems still persisting.
A vacume hose on the turbo had also burst but this has been repaired/replaced.
No lights showing any problems on the dash and nothing showing on the computer diagnostics.
Any help would be much appreciated as we are completely baffled!!!!