…while driving

It is a fairly old movie,  maybe set in the 70s? It was in color and not a big hit.  The couple who get together in the movie at first don’t get along at all but eventually end up having sex while driving. The last scene is their Volkswagon beetle driving away slowly and swerving back-and-forth because obviously the couple is once again having sex while driving off into the proverbial sunset. Must’ve been a rom-com of sorts.