i really need help...
 

I have an Audi A3 sline 2010. When slowing down and going down the gears the car seems to loss power. if its put into first it usually goes ok again sometimes needs to be restarted ive also seen a puff of black smoke from exhaust. It does not always loss power appears to get worse when car has warmed up. I had it on the machine four times and no faults show up. Please could someone give me some advise or have you ever heard of this.

What motor? The 2.0ts were prone to carbon build up problems, not sure if that could be affecting idling or throttle position issues.

Its 1.6. Would that mean EGR valve faulty??? Would that not show up on the machine..I think i have smelt exhaust fumes at times when idle..