I have a 2nd hand focus c max diesel auto 2004, there have been power problems lately and bad fuel consumption about 31 mpg urban. The power drops and the car will only rev to 3000 and then its very slow starting off and causes problems at roundabouts or pulling off in traffic. The garage put a new fuel filter and air flow meter on and it still doing it. Now the garage sais its a new turbo which is going to cost 700. anyone help.