Hi,

I have a 2004 Ford Focus 1.8 TDCI that is having some issues:

1. There's a noticeable lag between when you press the accelerator and when the car accelerates, once it starts going its fine but there's a 1-2 second lag

2. Occasionally when you accelerate, huge amounts of black smoke pours out of the exhaust and the car has no power, 10s later it just fixes itself and carries on as normal

Any ideas what the issues could be?