- 99% of the problem is the battery. 1% can be starter/spark plug. 7 e8 r% Q/ p4 Q3 D( \" ^1 d" I7 W- 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. ( S1 E2 e: q. v1 z7 k2 k- make sure there's gas left in the tank : t9 F* u0 J$ J" Z% _- 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.