At the base of the intake manifold, under the mixer there is a electronic injector. It has a plug with 2 wires going to it. Remove the valve from the manifold and hold it in your hand. Turn the key on and you should fell the valve vibrate. There should be a small amount of LP coming out of the valve. If it is not vibrating try cleaning with carb cleaner. If it still doesn't vibrate check to see if there is a voltage across the terminals. If there is a voltage, replace the injector.