my jeep wont start. it turns over but not start it worked fine the night b4.. a buddy of mine told me that the distributor cap gets moisture. especially in a rainy day like today and yesterday. i changed my distributor cap and rotor and the pick up coil. and still no start how can i check if it has a spark when its sunny and bright out side.... the jeep has a good battery. and the wires are in good condition... can it be a sensor... Oh and my jeep its a 97 TJ wrangler sahara 4.0 auto.