If you ran out of gas before filling up, your car may need a little help getting started. If you have a fuel injection system, turn the ignition on and off a few times without actually starting the car. This will pressurize the fuel system and assist in starting the car. If you have an old carburetor system, give the gas pedal a couple of pumps before turning the key.
Jump starting a car can get you out of tough situations, but it can also be quite dangerous. Follow these precautions before doing so: