I have my Q7 4.2 tdi..so car start is ok first time...when i am driveing all electrick goes off for less then half second and then all is ok..sometimes is ok for few minutes sometimes for few days!!after i drive car 20 30.min and i stop car again no electrick even to take key out of ignition..for few seconds then is ok...if i want start car after i drive is not start..but if i leave it 20 30 min will start ok...any one can help me?