motor run motor start.

Voltmeter is often a good trouble shooting tool. Read the voltage at coil +, with key in run, and start positions. Also check the coil -, when cranking, it should bounce up and down. If it is always down, then no spark. ... and when you release key it will fire ... and possibly backfire. Stuck low, coil - , wire short to ground , ignition module shorted, tach wire short.