- 99% of the problem is the battery. 1% can be starter/spark plug. ' T( p4 T" U/ U# O* k" b- if it's automatic transmission, check to see if the gear is set in park position. if it's in drive or reverse, you cannot start your vehicle. : N6 U1 e7 g' C& _* U9 A7 T4 \- make sure there's gas left in the tank 4 f% \3 I5 Z+ v- depand on how old your car is, it may have a computer built in to control fuel injection. if the computer breaks, you won't be able to start the car either.