When measuring the RPM of my '74 2.0. with conventional points, using a digital VOM I get twice the expected RPM values. Yes, I have the VOM set to 4-cylinder. I know what a 1,000 RPM idle sounds and feels like, so I am sure it is the VOM reading double. Analog meter says 1,000 yet the VOM says 2,000. What gives?
Ansbacher
So I don't have experience with the DVOM you are using, my DVOM that has RPM uses an inductive pick up that clamps around a spark plug wire.
Digital meters are more sensitive, check that you have good clean connections (especially the ground) and make sure your leads are not laying on or very close the the plug wires or coil wire. The high voltage in the plug/coil wire can create enough of emi that your meter could sense it as a pulse.
Jim
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