Hi. I recently bought a 2001 Audi A4 1.9 tdi. I took the car for a test drive and it was fine. The next day I travelled long distance with the car when during the journey I noticed that the car had lost a considerable amount of power. I took it to an auto electrician and it was diagnosed with "overboost". Since then the car is driveable but with not much power at all. Has this happened to anyone else previously? Or does anyone know what the problem might be or who can fix it for me?