DEAR CAR TALK: About eight months ago, I had Nissan put a new air conditioning compressor in my car. About two nights ago, I was driving and heard a snap, and my car started acting up and getting hot.

DEAR CAR TALK: We have a 2010 Volkswagen Jetta. The air conditioner takes at least 15 minutes to get to a cool temperature. Until then, it blows plain old hot air. Once it does get cool, it will stay ...