- Joined
- Jan 1, 2012
- Messages
- 8,546
- Reaction score
- 1,415
- Location
- Eugene, OR
- My Car
- 1971 Mustang Sportroof M code
The MSD distributor has a built-in ignition module, no points.
When the engine is cranking the negative terminal on the coil should pulse as the ignition module applies a ground, charging the coil, then remove the coil so the field collapses, creating the high voltage pulse to the spark plugs. If you connect a voltmeter to the negative coil terminal and crank the engine and the voltage on the negative terminal does not change, the MSD distributor ignition module is bad, or not connected correctly.
When the engine is cranking the negative terminal on the coil should pulse as the ignition module applies a ground, charging the coil, then remove the coil so the field collapses, creating the high voltage pulse to the spark plugs. If you connect a voltmeter to the negative coil terminal and crank the engine and the voltage on the negative terminal does not change, the MSD distributor ignition module is bad, or not connected correctly.