After a recent weekend away travelling in convoy. I was told that my focus is smoking during accelleration.. My oil level was down and I was concerned. I had it checked out and the o ring wasl leaking. the fuel injectors were sooted up.. He sorted this out and put some additives to the fuel & oil to clean it out. I was told to drive the car hard for the remainder of fuel left in the tank and this should stop smoking. This has not changed anything. It was 4000 miles since my last full service and a new triming belt was added. I just seem to lack power in setting off and in 2nd gear and it smoking as I accelerate before the turbo kicks in. In 3rd, 4th and 5th the focus is flying. I realised that I may have to see a diesel specialist but i was wondering if anyone else is experiancing the same problem.