Octavia II : Car Jerk when Cranking

I am driving an Octavia II 1.6L mated to a 6-speed Tiptronic Auto Trans.

The car has been driven about 15,000 km over slightly 1 year.

After about 5,000km of driving, I start to feel a slight jerk to the car when I start in the morning. The jerk starts to get worse along the way. Sometimes, it can be quite a violent jerk on the car. I drive it back to the dealer and, suspecting it to be the spark plugs, they changed it. It was then alright for a day or 2 before the jerk came back, but mildly. After another couple of months of driving, it became more apparent again. I drove back to dealer again and their mechanic tested the car. He announces that the vagcom shows no sign of problem and he then proceed to explain that the jerk is acceptable, as this is also experienced by other owners. Apparently, he sees this as an inherent problem with no solution. I used to drive Octavia I, 1.6L Euro 2 specs, for 3 years 100,000km and the starting has always been smooth. I therefore find it hard to accept the explanation. I am therefore seeking the opinion of other owners of this similiar car whether they are experiencing the same situation?

Other than the issue above, my engine's rpm also fluctuate slightly during idling and vibration can sometimes be felt on the steering wheel when I turn on the air con and my car is laden with passengers. The problem is, these are intermittent issues, and they do not crop up all the time. Appreciate any advise on these issues.

Edited 7 April, 201016 yr by sbnp