1973 Mustang 351c 2v Died While Driving - Need some help

Greetings everyone! Have a brain hurter here.

1973 Mustang 351c 2v died while I was driving home after getting an upper ball joint replaced. Never had issues with it like this before. Couldn't get her restarted and had to have the big girl towed to my neighborhood. Symptoms and current troubleshooting steps are below:

Symptoms:
-Car died while driving an uphill, couldn't restart the girl but she cranks just fine. Now on a flat level, same problem.
-Car cranks but does not turn over.
-Had previous symptoms over the past two weeks of the Alternator light flickering (no tach or gages, just indicator lights). Now, when placing ignition into ACC, the light should be bright but is now barely visible. Temp light works fine while cranking. For some reason, the "fast" wiper setting does not flow smooth and stops midway before restarting. Also, when hazards and lights are turned on, there is significant flickering in the hazard light indicators (especially the left side). Never had this issue before now.

Verified good:
--I have 3/4 gas tank and it's making it into the carb when throttled. New fuel pump 3 months ago and replaced the fuel filter.
--Battery good. New battery replaced (old one needed to go and was too big for the tray anyway).
--Replaced starter solenoid (verified good through resistance and voltage readings).
--Ground connections good throughout vehicle.
--No blown fuses.
--Good voltage readings at ignition resistance wire to coil. Replaced dizzy and coil with pertronix flamethrower 3 a couple months back, been running like a beauty.
--Good resistance readings and function checks on ignition coil and wires. New dizzy appears to be functioning properly.
--Verified timing chain is functioning, and no timing skip occurred (piston 1 at TDC where it should be).

The only things I haven't changed are the alternator and voltage regulator. What's hurting my brain is none of these should impact the car from starting, though it may not run that long once it does. Any help from the experts here would be appreciated.

Go to any parts store and get a spark tester to verify spark at the plugs:

I have often seen where the red wire with green stripe has a bad connection at ignition coil (check the terminal), or this wire was damaged somewhere along the path from starter solenoid to ignition switch to ignition coil. There are some wiring diagrams describing this ignition circuit.

Use a volt meter to check the voltage of this wire at the ignition coil, should be around 12 volts when key is in run position.

I had installed a pertronix III at one point. Took a shit after about 2 months. I believe other members here have had similar issues with the Pertronix III.

Update: no spark using the tester. All good inputs to coil. Have a new coil coming Wednesday. Appreciate the help and will let you know what happens. Didn’t think it would be the coil - it’s only 3 months old!

Also check on spark  to the distributor. Pull the center wire off the distributor cap, plug it into your spark testing tool (grounded of course). If by chance you get spark during cranking, your problem is the rotor or cap, not the coil.

Check for possibly sheared distributor gear roll pin

73pony said:

I had installed a pertronix III at one point. Took a shit after about 2 months. I believe other members here have had similar issues with the Pertronix III.

Click to expand...

I recently added a Pertronix I and their Flamethrower 3 ohm ignition coil into our 73 Mustang Convertible just so I could show a fellow enthusiast how to do the installation, as well as provide him with rewiring schematics for the system (both the Pertronix device and the new coil required full switched power). So far the engine is (still) running well. I do plan to purchase a backup Pertronix simply as a precaution.

For anyone interested in how I installed our Pertronix I and Flamethrower ignition coil you are selcome to look at the YouTube video Lynda and I put together. In that video's information section I provide a link to some related installation material, which includes some annotation from me.

https://youtu.be/_qGVhoFnJ50

Good afternoon!
I had the same problem with my pertronix 3.
It’s just not reliable. I’ve changed to a sniper’s efi and distributor. It’s another life!

Well, even though I am using a Pertronix I (original design, I am not covering the Ignitor II or III units in this post, I do not know the voltages they require), I think it would behoove me to carry a spare Igniter in the glove box, and a screwdriver. I have the correct voltages at both the Igniter module and the Flamethrower ignition coil. As I understand it the reason the Igniter modules for the original Ignitor (not sure about the II or III Igniter modules) tend to fail is they either overheat or the incorrect voltage is used.

I saw what I felt was an ambiguity with their directions between the Igniter module and the Flamethrower ignition coil. The Flamethrower said for the 3.0 ohm ignition coil (like I am using) the positive primary terminal needs to be switched battery voltage. Other resistance values may require less voltage (using the factory resistance wire). The Igniter module is also supposed to use switched battery voltage, not the lower voltage from the Ignition System's resistor wire. For folks using the own ignition coil that can get confusing, as Pertronix says to use the resistance voltage for oem ignition coil's yet the Igniter still requires full battery voltage from a switched source. On one YouTube video after another I saw folks connect the Igniter module leads to both the positive and negative primary terminals on oem ignition coils. It works, but the running voltage to the Igniter module is too low, which apparently will cause problems later on.

Anyway, to reiterate for anyone wanting to see how I installed the Pertronix electronic ignition (their original version), along with a Pertronix Flamethrower, it is on my YouTube video on the following link. In the description I have another link where you can get the Pertronix installations with my annotations where I try to clear some possible ambiguities, or points of potential confusion, up.

https://youtu.be/_qGVhoFnJ50

Update: replaced ignition coil and it fired right up.

Issue now is I am curious as to what caused it. Was it possibly just a faulty coil, or is there something else going on that will result in the same a few months down the road.

One question I have is if I’m supposed to have a pertaining ignition module/box paired with this igniter 3 system. Limited research shows it works both ways, but am wondering if having the module with make it last longer.