These links will take you to videos where you will see cars actually running on water.  Actually they run on the gas that is created when the hydrogen and oxygen in water are separated.  The only exhaust is water and oxygen.  This not only eliminates pollution but adds much needed oxygen to the atmosphere.

Stanley Meyers Water Car   

Denny Klien Water Power

Danial Dingel Water Car    

Japanese Water Van

Japanese Water Car
Why are we still using gasoline?