I think you're correct John. Either the switch was left on the probe setting (I've done that a million times lol) or it's a bad coil. But the probe sounds like it's functioning well if it works on the stock coil. Most of you guys are electronics guys, so you know how to elliminate causes when searching for the problem. If the probe works on one coil and not another, then it's probably the other coil at fault. Try it again Sal and make sure it's tightened good, and the switch is not on the probe setting. Let us know what happens.