Actually, that isn't quite right. The patent itself would cover the entire business case to be made for such an invention, that is the whole car, or any possible way in which the engine might be used.
The INDEPENDENT CLAIMS in the patent would include all of the things you listed. A solid, enforceable patent will have independent claims specific enough to exclude as much prior art as possible, but that doesn't mean any prior art would invalidate the patent. Your super efficient engine design, for example, could include components like a fuel injector that people have been putting into engine designs for decades, but that doesn't mean it isn't patentable. Your patent should at least reference the prior art, however.
Here is where lawyers like to get general. A super efficient engine is novel, but it is a useless novelty, unless you put it into a machine, such as a car, that performs a useful function. That is where DEPENDENT CLAIMS come into play. You want your dependent claims to be big, broad, sweeping and general to cover as many business cases as possible. This process invariably invokes big giant buckets of prior art. All of which you need to reference, of course.
I think it is high time for /. to stop cherry-picking lawyer-speak from patent applications. If your invention builds off of previous inventions, like all inventions do, and the patent application is written correctly, then there is always going to be some set of broad, sweeping claims which, when quoted, will send the comment section into a rantfest.