Starting spark frequency? (ignition issues...)

How to check spark

First it is important to understand how Mopar ignition switches work. The "run" position is hot in run, and feeds power to the coil through the ballast. On older "5 pin" ignition boxes, which require a "4 pin" ballast, the second ballast also feeds reduced voltage to the module, as well as "full battery" V to one other pin

The "run" voltage GOES DEAD (a function of the ign switch) when twisted to "start." The ONLY voltage to the ignition system in "starting" is provided by the IGN2 circuit, normally brown, which goes to the coil+ side of the coil, and feeds "full battery" to the + side of the coil. It ALSO "backfeeds" V through the ballast and to the module during this time. That is, during start, the module works on reduced voltage

The reason I'm telling you this is that if you test spark and you bypass the starter relay with the key "in run" this sets up a "false condition" which can lead you down the wrong path. ALWAYS try and test by using the key to crank, unless you realize the difference

So "rig" a spark gap out of the coil tower using a solid core wire, not a radio resistor one, and use a large gap plug or other means for a gap. Crank using the key. A properly working system will make nice blue sparks at least 3/8" and typically more like 1/2" long



Always suspect the dist. connector. Turn key to run, pull dist connector apart, and rig a spark gap to the coil HV tower. Take the engine harness half of the connector and repeatedly tap the bare terminal of the connector to ground. A nice single "'snap" spark should happen each time

Dont be afraid, generally, to wiggle test connectors, and to work them in/out several times to scrub the terminals as well as "feel" for tightness. There's even been a few guys here have had trouble with the big connector on the module, so don't put that out of your mind.

The module absolutely MUST be grounded to operate. Scrape around the bolts remount using star lock washers

Inspect the dist. reluctor/ pickup for rust/ debri/ damage. Inspect the shaft for wobble and loose bushings. Hook your multimeter to the dist connector and spin dist. or crank engine. On AC low volts, the dist should "generate" about 1v AC