Dumping video links about GM DIS (Actually DIS2. And before you ask, Yes, there is a "DIS 1" but only a few V8 used it and god help finding parts or data for them.)
From Wells/Airtex now under WVE brand at many parts outlets GoTech is all Wells Training/Sales videos https://www.youtube.com/c/GoTechTraining but can be hard to find a video you need...
Wells Distributor - less ignition system, DIS, Training with Sgt. Tech https://www.youtube.com/watch?v=kgHV5hipyPM How DIS2 works. Scan codes only apply to OBD2 cars. OBD1 cars do not report misfires. ⚠️ Many people don't think "Sgt. Tech" is funny even years before the "woke" crowd happened. Like late R. Lee Ermey gets on many nerves for over doing he's Drill Sergeant act or just for the act/cartoon for a non-mil issue.
Wells Distributor - Less (DIS) Ignition Testing and Troubleshooting https://www.youtube.com/watch?v=2woQT1eOy8U May help some to find DIS problems. This often won't help finding a coil that "shorted" HV side to LV side but may help what cause a coil to "Flash over."
⚠️ Not only DIS but HEI and often ignition coils often fry from same reasons. Even lawnmower and other small engine coils. (Maybe more so now w/ B&S and maybe other small engine "new" coils that doesn't need points.) You need some type of spark tester to safely test a coil or isolate a cylinder. Even an old plug w/ a wide gap touching/clamp to the engine is better then nothing. Never pull HV wires to disable an engine or trying to find problems like covered in this thread... https://www.fiero.nl/forum/Forum2/HTML/145872.html
------------------ Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should. (Jurassic Park)
