[herr_oberst]

I got to thinking after watching this; Leno is probably as well-versed as anyone out there as someone who can quickly suss out a problem while he's out driving. He's totally nonplussed here, doesn't even attempt to pull over before he has the issue narrowed down to the eventual problem.
This kind of thing is probably a weekly event for him.

My MO in these situations is always to immediately find a place on the side of the road to land so I can 'get out of everyone's way'. I think getting out of anyone's way is the last thing on his mind, he wants to solve the problem with the car, and stopping at the side of the road is not going to help him do that.