my 2000 audi A8 has failed to start after stopping and starting for 2 hours. i was advised by dealer to leave it for an and try again, this did not work. 7 hours later the engine started and ran perfect. the following day out shopping it did it again. being christmas eve i had it towed to dealer where it sat for 2 days. dealer phoned to ask what was wrong as the engine fired up right away and was running perfectly. I can,t trust it till some body finds out the problem, any ideas anybody

 

maybe the crank position sensor