Hi, I had taken my Audi TT 1.8T 2004 for a Dyno test. Car was running good on the test. After the test i parked the car for about an hour then drove it. It was jerking while changing gears, so i had to keep putting the car on neutral while trying to get home ( Its a Triptronic Transmission ) . After the Jerking the car would turn off so i had to start it again and go through the whole problem again.
What could be the cause of this?

Thanks