mk3 tdi popping and smoking

[nogama3]

travelling to work today i had to overtake a saxo vtr which was going to slow round the countryside for my liking but at 40 mph in 3rd car car gave a small jerk and a puff of smoke which concerned me. Is my car timing wrong or is my air mass meter a goner or am i barking up the wrong tree? any ideas my brethren.

[golfvr6]

likely to be as you said, airflow meter, or pump timing is out.