Driver pits on last lap with 2 liters.

Both of my drivers are battling for the win at Australia, both using kers.  They come down to the last couple of turns neck and neck and one of them decides to enter the pits.  Both had the same fuel, 2 liters left.  The driver that pits just slows down and continues right to the finish line  He never stopped at the pit stall.  He still finished 2nd, but  if it was a tight race with another team I would have been screwed.  Why did he do that?

It happened to me a while ago. I think it's related to low decisions of the driver in question.
You just have to be on lookout when he does that again, and deactivate pit button if it lights green.
Then it won't happen no more.

His decisions are at 19.