What type of ignition system is it. Is an old standard type using ign points and coil or does it have an electronic control module. In any case the points are an intermittent ground allowing current to flow through the coils primary winding and then stopping it so as to collapse a magnetic field in the coil. If the points are dirty of the wire interrupted or if it has a condenser / small metal can hooked to the points the circuit wont work. If it's not electronic it will be easy to test. Using a test light attach the clip to the engine in a non painted surface and turn the ignition on. You will have removed the distributor cap prior to this point. Points closed the light should not light up as the voltage is going to ground through the points. Points open the light will light up. If this doesn't happen you need to discover why and resolve it. If the car has an electronic ignition system do not use a test lamp as some systems don't respond well to a low impedance lamp being used..... that means a standard test light.