My biggest gripe is not including the link to the accelerator pedal. If you don't know how pushing the pedal makes the engine spin faster, do you even have a basic understanding of how engines work?
Yeah, I'll give you that one. I think it does open a can of complexity, though, what with explaining intake vacuum and all. OTOH, it would solve the mystery for those that know what the accelerator cable attaches to, but have no idea how opening a plate makes "vroom vroom" noises.
