First time it happened couple days ago. Basically, everything is working just fine besides speedometer. After I started the engine and moved off, just didnt work. I thought it is some kind of computer error, so I have disconnected battery and everything seemed to be good. Today when I was driving to work, everything was fine. But on my return journey speedometer did not work again. What is it? Please help. I drive audi 100, L reg., 2.8l quattro.