To you, does a clean automobile just seem to run better?

Yes, it runs like a dream.

I don’t know about running better, but it sure makes me feel good when it’s clean.

Thanks Dibley.

I know it doesn’t but it just feels like it does!

I think it’s psychological—the same as when you are wearing new clothes that you like or when you get a fresh haircut.

The Vulcan Science Directorate has determined that a clean car has lower drag than a dirty one and reduced aerodynamic turbulence on its surface, possibly reducing noise as well. It is also lighter than a dirty car, together with the lower drag decreasing petrol consumption and increasing acceleration, even though you probably will not notice the latter.

Mythbusters covered this. The difference seems so small I doubt you would notice. Maybe they properly inflated your tires while you weren’t looking. That will make a noticeable difference.

The inside of mine has to be clean; I can let the outside go a bit.