2000 Jetta shut off while sitting on a hill

your car flooded. It can happen with audis and vw's when parked on an angle. Try taking out your spark plugs and clean your mass air flow sensor. also check your crank case hoses and all your vacuum lines. Once your car has sat for a day it will probably run like usual but do these couple things first and check for water build up in your throttle body and vacuum lines. if your engine does not run long enough it builds up water in the intake because it does not evaporate it. This is why its best not to just do a lot of small trips and not let your car hit its regular operating temperature

Disable fuel and distributer remove spark plugs turn over in 4 second increments about 5 times plug in fuel system and distributer put in the plugs double check the connections and fire the motor.