On Going no start

Get as far down to the basics as possible to check spark. You want to use a WIRE core coil secondary wire, even (for testing) if you have to temp use a low voltage wire, just hang it in space

"Rig" a test gap, either buy a gap type tester or open up a good spark plug so the gap is wide

you might even unwire the coil / Pertronix conection and just jumper battery power direct to the coil/ pertronix.

Make CERTAIN the dist. has a good ground (hold down bolt loose? == poor ground, maybe, that is where the Pertronix gets power

So with power jumpered to the Pertronix, and cranking, you should get nice hot snappy blue spark at least 3/8" and typically 1/2"

There is always a possibility the coil is weak. Coils do not necessarily go completely bad. Heat often causes coils to 'come and go.'

There is always a possibility the Pertronix has a problem.


So if you are getting 11V to the Pertronix during cranking and no good spark, it HAS to be either the coil or the Pertronix. Again, make CERTAIN the dist. is "tight" for ground

If that part works/ good spark, then concentrate AKA are you really for sure getting 11V to the coil/ Pertronix during cranking, with the wiring properly connected?

Once again, I think Pertronix normally recommends a coil with a ballast

WHY IS THE BALLAST USED and why is it "good?"

You hear a lot of "bad" about ballasts, but frankly I have not replaced very many. I am 75 had mopars back in the SEVENTIES

The ballast, when the car is running and charging at 14V, keeps the coil at maybe 11-12V, "it varies."

Due to the key starting circuit, IE IGN1 "run" and IGN2 "bypass" the coil ALSO normally gets about 10-11V during STARTING

So if you eliminate the ballast and to to a 12V coil, NOW what happens is the "12V coil" (a misnomer, they are REALLY a 14V coil!!!---Now that 14V coil is only getting 11V during STARTING. So keeping the original ballast and ballast type coil combo in there causes a hot spark during cranking.