You can wash your engine with a hose. You've gotta blow the carbon out of your car's engine by driving fast and hot and near the redline. These little pearls of wisdom shared by uncles and grandpas from sea to shining sea aren't exactly myths. They may not be great ideas, but there's also a kernel of truth to them — if you learned to drive in, say, 1968. But not everything you know about how cars work, especially about how old cars work, is even near true. Many of the things we know about old cars are about as mythological as the Cyclops and the unicorn. Let's strike-out a few of the more pernicious myths before they spread any further.