2003 Monte Carlo 3.8 liter, cranks no spark?

3 months ago, the engine had an intermittent no start, crank o.K. Now its march and the engine was bucking and jerking at idle in park and blowing a little black smoke. Now it won't run at all. It has no spark.
Trouble Code p/1374 Crankshaft Position Sensor 3x reference circuit was set.
The 3x wire had no rpm while cranking on my scan tool. It only happened once. I redid the test and got something like 178 rpm while cranking. The 18x rpm registered the same rpm. I
The sensor is getting 10 volts while cranking from the ignition module like the repair manual says. Sensor ground is good.
My car has two signal wires from the sensor to the ignition module an 18x yellow wire, and a 3x light blue with a white stripe wire.
The ac cranking voltage of the 3x wire was 1.7 to 2.8 volts measured at the ignition module.
The 18x wire shot up to 3.5 ac volts while cranking with no minimum voltage. I measured at the ignition module. Wouldn't the voltage drop when the gaps in the reluctor wheel pass the sensor? Is a digital multimeter too slow to read the voltage? I have a snap-on multimeter, model eedm504d. Do you need a lab scope to pick it up or is my sensor bad.
Can you tell me the proper ac cranking voltage specifications for both wires.
Could it be my ignition module? The module has full battery voltage at the pink wire and the black with a white stripe ignition module ground wire is good.
I await your reply. Thank you, Bruce Duncan. Phone 978 246 3523.