If a system called "impulse" doesn't have anything to do with what an impulse is... that's just wrong.
Just to be contrary, I'd argue that the expression "impulse engine" could easily originate from a trade name, just like "diesel engine" does. There'd only need to be a very vaguely similar engineering principle behind the modern impulse (diesel) engine and the original creation of the Impulse Corporation (Rudolf Diesel).
Whether the same holds true for "warp engine" is an interesting question, too. These are very complex machines with undoubtedly complex operating principles: it might be impossible to express the principle properly in the name, so deliberately improper choices are made instead. Engineers usually do make every effort to be funny... Or cool. Or both. (Usually, they think the two mean the same thing.)