Hi my 1997 a4 has decided to give me grief. My wife reports that she heard strange noises on her way to the shops, after shopping the car would not crank over, I have 12.4 volts at the battery and lights etc work, the car also runs when push started.Is itpossible that this is a starter moter fault and the noise was the starter overrunning or does anyone have any suggestions. troubleshooting suggestions will be greatly appreciated

 

Sure sounds like a starter motor or battery ground issue. The next time it acts up, tap on the starter solinoid with a hammer, if it magically starts cranking then the starter is bad.
Also remove the battery and check the main ground to see if its tight and the wire isn't frayed.