The film concerns a clean-cut teen intrigued by an older man who happens to own an outlawed personal car which he's stored in a barn. The plot of this is in-line with other crisis movies of the time like "Americathon" which reflected the belief that the structure of America was crumbling and authoritarians would take-over. There were dozens, if not hundreds of apocalyptic or semi-apocalyptic movies like it, culminating with the magnificent "Mad Max."
Then, the inspiration was President Jimmy Carter's oil-crisis of 1979 and the ridiculous idea of "peak oil," while today it ties in with attempts to control private car ownership/usage to curtail CO2 emissions. However, the result is the same, control by an elite for whom the rules don't apply.
The movie unfortunately couldn't make much of a statement back then with a draggy script, a frighteningly bad song accompaniment and NO budget. The only thing it had going for it was Darren McGavin and the car. Today, a similar story might be based around noted author Michael Cricton's book, "State of Fear" which deals with the climate "crisis." One of the few Crichton books not make into a movie by Hollywood.