Quote:

Because Swedes will drink anything

In this case however I believe he was wishing to portray the close bond the driver felt with the car i.e. the sharing of fluids and the desire to be one with his rusty steed. Additionally there is an intended irony with the youthful exuberance of the driver combining with his mechanical inexperience (his awkward actions as he opens the bonnet/hood) leading to his performing the taste test as you would for a fine wine or food. In this example you could also extend the metaphor and say that the director wished the audience to understand that this car has been 'cooked' as a result of the driving we have seen and is now 'well done' and very tasty.