Why the hell should we allow then to use the road if they won't even let us inspect the engine?

How do you think a car gets approved right now? Do we take it apart? Do we ask for the design calculations of how they designed each piece?

That isn't what happens. There is no "audit" of parts or the whole. Instead, there is a series of tests to determine road worthiness that everything in a car has to pass. We've already accepted a black box for the electronics of a car. You don't need to get approval of your code to show that pressing the brake pedal causes the brake lights turn on; they just test it to make sure that it works.

We don't audit the code already for life critical software already. It is all liability taken on by the manufacturers and verified via government testing of the finished product. What is an audit going to do when we don't it already?