I was out in the Dart, sitting at a light in gear, and the idle slowed down a bit maybe 100-200 rpms, from 900 to 700, to where I had to give it some extra gas to get it up where it belonged.

As I pulled away, all of a sudden, the car died and I coasted to the side of the road to be towed home.

When I try to start it, it spins normally but never seems to get a spark. There is gas in the carb so fuel is not the issue.

My dad is coming over later and we can verify that there is no spark coming out of the coil. But I couldn't help wondering if the idle slowing down at the stoplight was a clue as to what may have quit.

The ignition system is an Accel 300+ box and coil, and a Summit billet electronic distributor. It has been running fine with those parts for years. There is no ballast resistor. I checked the fuse in the ignition box and it was fine.

So from the idle slowing down and then something quitting and resulting in no spark, does it sound like anything in particular? Coil?

I also plan on pulling the distributor cap to see if I can spot anything going on in there.

Don't know if this will help but here are the instructions for testing MSD box and dizzy.

If for some reason you feel that you have a non-functioning MSD Ignition Control, this simple test can be performed to
determine if the MSD Ignition Control is functioning properly.
If triggering the MSD using the magnetic pickup connector (Violet and Green Wire) of the MSD:
A. Make sure the ignition switch is in the “OFF” position.
B. Remove the coil wire from the distributor cap and set the wire 1/2” from ground, such as the intake manifold
or cylinder head. Do not crank or attempt to start the engine.
C. Disconnect the magnetic pickup wires from the distributor or crank trigger pickup. Turn the ignition switch
to the “ON” position. Do not attempt to crank the engine.
D. With a small jumper wire, short the Green and Violet magnetic pickup wire going to the MSD together several
times. Continue to step E below.

If triggering using the White wire of the MSD Series Ignition:
A. Make sure the ignition switch is in the “OFF” position.
B. Remove the coil wire from the distributor cap and set the wire 1/2” from ground, such as thee intake manifold
or cylinder head. (Do not crank or attempt to start the engine.)
C. Disconnect the MSD White wire from the distributor’s points or ignition amplifier. Turn the ignition switch
to the “ON” position. Do not attempt to crank the engine.
D. Tap the White wire to ground several times.
E. When the magnetic pickup wires (Violet and Green) are shorted together repeatedly or the White wire is
tapped to ground, a spark should jump from the coil wire to ground. If there is no spark substitute another
coil and repeat the test. After repeating the test with another coil, if a spark still does not occur from the
coil wire, remove the small “Red” wire from your MSD going to your ignition key “On/Off” source and attach
it directly to the positive (+) terminal on your battery.
NOTE: Attaching the “Red” wire directly to the positive side of the battery will cause the engine not to shut off when the
ignition key is turned off. If attaching the wire to the positive side of the battery cures the problem, then you must
find a different “On/Off” 12 volt source for the small “Red” wire from the MSD. If after all of the above tests have
been performed and no spark appears, then your box is in need of repair.