[Ar-Curunir]

Optimisation and Search problems are not fundamentally different; one can usually translate a problem from one world to another. For instance, take your optimisation problem and rephrase it as:

Here's a value of the fuel efficiency; find me a setting of the parameters that achieves a fuel efficiency better than that.

It's now a search problem. To find the best fuel efficiency, just binary search over possible values of the efficiency.

Where D-Wave differs is that you can only solve a particular kind of optimisation problem, and this kind of problem can't encode general computation. General quantum computers can solve general computation problems, not just the simulated annealing of D-Wave QC.