eng1 fuse blows after 10 min driving ,code po102,have installed 20amo circut breaker w/ test light to feed side , breaker doesnt trip while in idle, or with key in on position, only serms to after driving , ran a voltmeter to feed side of fuse holder (no fuse) get readings from .01v to .9 v mostly higher readings after driving usually .01v when cold, is this a short?