Hiya, I have an A3 TDI 1.9 2001 reg, when I start the engine from cold it starts to hunt, the revs go up and down slightly. Then after five minutes or so it clears. It has been checked out at Audi and the fault code came up with a faulty temperature sensor. This has been replaced but the problem is still ongoing. Has anyone got any idea as to what maybe causing this problem or any idea on how to fix it? Thanks in advance.