Truck drove fine, now it won't start

1987 Ford F150, 5.0 302

I recently replaced the pickup sensor and set the timing. Today I drove it about 20 miles, 10 to the gas station and 20 miles back. It started rough in the morning and at the gas station, but still fired up on the first try. I had a no start problem last week when I drove it about 10 miles. It would turn but not start, then after about 5 minutes it fired up. I turned it off and on 6 times, all successful starts.

However, today I parked at home, turned it off, then tried to start it. There was a slow growl for 3 attempts, then I’d hear the fuel pump prime and a click from the right side of the engine. I tried a few times over a ten minute span to start it, and just prime and click each time.

I have a suspicion that the ignition module is the culprit, but the starter could have finally died too, I suppose. The starter solenoid was replaced last fall. New plugs, wires, cap, rotor, ignition switch, and ignition coil over the past year. The battery after parking today registered 12.31 bolts on a multimeter. Any ideas? I haven’t tested the starter, but I don’t know how (I will research it though)

Ford ignition modules of that era were problematic. I had 4 ignition modules replaced in my 89 Ford Tempo because they couldn’t take the heat. If you let the car cool down for an hour, it will start right up.

slow growl when cranking?

What is the battery voltage during cranking?

I’ll be able to try and start it tomorrow. 4 modules? Dang.

Yes, like it’s struggling to start. Turning very slowly, a growl was the best description I could come up with