thats to show internal resistance of coil. Pretty good indicator of a coils health. As for the no spark condition, you could set the meter to OHM and touch the leads together. the needle should swing to other side (0) showing a short. Now if you lift and attach the negative coil lead from he pretronix to one side of multimeter and the other to ground and crank the car, you should see the needle swing 4 times per engine revolution. they will swing quickly or may just show a wiggle on the needle. If its a digital , you may see the resistance value go from 0 OHM to some value very fast. If you cant see the digital move, use a wrench on the crank and turn it. The pertronix just triggers the ground connection through a transistor instead of breaker points. It actually goes open to trigger the coil to fire. Also you should set the multimeter to DC volts (50 scale) to measure the voltage to the positive side of the coil.
