I am stumped. I have a 1998 a4 quattro. Anytime its get under about 30 degrees outside, the car will not turn over. The lights come on, everything works, but when I turn the key, there is no tick from the starter or anything. I have the battery checked and it checked out ok. The battery has 690 cold cranking amps. I am not sure what else it could be. It was 37 today, and the car started right up.

 

wow, no one knows, or has suggestions?