Hi all. Yesterday i had my golf mk4 tdi pd100 timing belt replaced. I bought a timing belt kit and waterpump from bosch. A mechanic installed and today I went to pick it up. Immediately as i went to start it, it didnt start Immediately but instead there was a second to start the engine. As it started the engine made a much deeper noise. It sounded much louder and deeper as if it was like a tractor. When i started driving it i noticed that it had much less torque and wasnt pulling well. While all this the engine as i went to drive away was making deeper sounds. As I continued to drive it i noticed that it wasnt pulling and was very slow and while i was in 2nd gear and got it up to 3k revs then it was workign like before i had changed it and it was pulling like it used too. During driving it on almost any gear i noticed that when it went up to high revs to 3k and over it was working as it used to. Anyone have any suggestions on whats causing this. Thanks very much.