Peeing off the side
deer
It can lead to an accident
Check timing/timing belt
Change the fuel filter first,
why does it matter if you're driving down a hill? At least it didn't cut off when you were driving up a hill? And I don't know why it would cut off I'm 13.
Check to see if you are getting fuel and spark
speed sensor
it is either the erg valve or the timing is off.
Check timing belt
perhaps if it was loose or the conductor was cracked.
fuel pump?
Press the brakes or down shift