Everytime i go to start my jeep it makes an overcranking sound, even though i am not over cranking it at all.. I will try to start it over and over again and it continues to make the over cranking sound and sometimes it will make an audible popping sound. Sometimes the jeep will start first try perfectly without the over cranking sound.. when it does eventually start it will start but first it will make the overcranking sound.. what could the problem be? I replaced the ignition switch that did not help. and i am getting ready to replace the starter here in a few days.. Any idea what else it could be?