White smoke when accellerating in lower gears

Hi

I am getting white smoke when pulling away in lower gears, once I am in top gear and cruising normally then there is no smoke, other symptom is I am getting a slight lag on the turbo. Not sure why white smoke have been using slick 50 fuel additive to keep injectors clean and will be using slick 50 additive on next oil change, would the lag on the turbo indicate a problem and be causing the white smoke?

Would be grateful for any information or if anyone else has had the same problem.

Alan