I have a Craftsmen digital voltmeter. I was testing the spark plug wires/coil on an old motorcycle I have and I think I screwed it up. I connected the positive lead to the spark plug wire and grounded to the engine case. Hit the starter and the display went haywire and then blank. I checked and replaced the fuse, put in a new battery and still nothing. I discussed this with my neighbor and he told me you cannot test "pulsing" power sources with a digital voltmeter, you have to use an analog. Is this correct? Is my voltmeter toast?