1991 mercruiser 3.0. Whenever I hit my power trim it causes the engine to miss. The boat runs fine for about 15 minutes before doing this. It will eventually get to the point that the engine will quit and not restart. I think I have traced the problem to the trim units on the outside of the lower unit. The wires are all frayed and the insulation is cracked in several places. If I get in the water and wiggle the wires, it will sometimes restart and run good for awhile. I have tried disconnecting the power to the tabs, but it made no difference. Will removing theses tabs help ? I suspect they are shorting out the ignition by backfeeding thru the gauges. Could I just disconnect the trim guage? I am stumped. Been fighting this problem for three tears. Everything electrical has been replaced.