I don't really think that there's any reason you can't like cars and be a socialist. I like cars, working on them, getting old shitboxes running again, but I don't think that it should be basically necessary to have one to participate in society. Most people should be able to get around via public transit, and I believe that most people would if given the chance because of just how much cheaper it is than personally owning, fueling, maintaining, and insuring a car. But people who want cars because they're cool and fun should be able to have them like any other enthusiast or hobby machine, like a ham radio. And besides, the emissions from car enthusiasts in a socialist society with mass public transit would be negligible.