Do they work in cars?

While wandering the aisles of the local auto parts store this past weekend, I started reading the labels on a bunch of those commercial fuel system cleaners.  You dump the container into your full auto fuel tank, and presto, your injectors, valves, etc., are supposedly magically cleaned and freed from harmful deposits. With all the known issues with fouled plugs and valve deposits in our big Continental engines, is there any reason this wouldn’t work in our aviation systems as well? (Or is this a taboo for some reason in our application).