Okay yesterday I drove my jeep to a friends house, it started just fine....hooked the tow bar up and towed it to the trails....got to the trails and the thing would not start....we tested it and it seems that 12 volts is going all the way to the the coil but it stops there....when trying to crank it the main wire coming from the coil has no spark....we replaced the coil twice and still nothing...any ideas anyone? It will turn over but just not fire.I have a amc 304 with a standard ignition syetem.I have heard a lot of people say get a spare ignition module because they can go bad so easily, what are the symptoms of one going bad?