I drove my ‘84 GL (Weber-converted 4x4 wagon) to work yesterday, and it died before I could shut it off after parking and idling maybe 20 seconds. I immediately tried starting it, which it did after a cranking longer than usual, but died again and then wouldn’t start later in the day. It’s cranking fast, it’s getting fuel, and the choke is operating correctly, so I think it’s a spark issue. 

The plugs have probably 1,000 miles on them at most, but they’re the only ignition component I’ve replaced since I’ve owned it. I went back to try to diagnose it today, but didn’t have the right size plug wrench on hand, so I haven’t pulled them. I took the distributor cap off and found a bit of reddish dust inside and a little play in the shaft - maybe 1/16 in. or less. Would that amount of play be enough for it not to run?

I also checked the coil with a multimeter and got a reading of 1.5-1.6 primary and 10.2-10.3 secondary. Not sure if I did that right. I’ve hardly used a multimeter before and haven’t had to diagnose any ignition troubles till now.

Any opinions and/or advice would be greatly appreciated. Thanks!

See if you are getting spark at the spark plugs. Pull a plug and ground it, have someone turn the car over and look for spark at gap. Try spraying starting fluid into the carb.

So I tried starting it while spraying some carb cleaner down the throat of the carburetor, but didn’t get even a sputter. No spark with one plug out and grounded while cranking either. My voltmeter showed 20.6 volts at the coil positive and negative terminals, voltage at the coil output, the other end of the coil wire, and at the distributor cap (only after a few tries though, so not reliably?) while cranking. No voltage reading at all from the plug wires while cranking. Oh, and the spark plug I pulled looked fine. I’m thinking it may be time to buy a new cap, rotor, and wires.

Points or electronic ignition? 

Electronic ignition modules can die from time to time. But sometimes they die because the coil dies and takes out the ignition module with it. 

If it’s a points system, check that they’re working as they should and that they’re correctly gapped. 

I don’t know what that inch measurement is, nor do I know what is the tolerance for the shaft play. If shaft play was an issue in the dizzy, you’d experience other frustrating running issues such as inconsistent running, and probably an idle that’s all over the shop too.

Hopefully this helps. 

Cheers 

Bennie

Thanks, Bennie! It’s got electronic ignition, so I guess it may be the ignition module. I just put a new cap and rotor on today, and it still won’t start, so I guess the coil and ignition modules are the next things to look at.

I haven’t checked the resistance of the plug wires yet, but I can’t imagine they would just suddenly get so bad as to cause it not to run after running fine earlier the same day. I was planning to replace them though, but just haven’t managed to get NGK wires yet.

Also, while replacing the rotor, I got another look at how much play there is in the shaft, and I’d say maybe 1/32 inch or 1mm. I did have the idle bumped up to around 900 rpm because it was rough at 700-800 - maybe that’s why? I am skeptical though that it would be the reason it won’t run now though.

One more thing I just thought of: I think my voltage regulator is shot. My gauge showed fine voltage at idle, but often way high while driving at much above 2,000 rpm. I’d turn the fan up to the third setting, and with the headlights on too, it’d drop to where it should be. This has probably been going on for the last 600 miles.

Update: I do have spark at the coil wire and at the plug wires, but it is only a weak orange spark, so I’m planning to pick up and install a new coil tomorrow.

No harm in trying a new coil. Having spark is positive. 

That voltage regulator pump too much into the system will kill things so it’s worth getting that sorted before anything else new is swapped in. 

Cheers 

Bennie

Bennie, you convinced me that sorting the voltage regulator issue out first was the way to go, and I’m glad you did. I waited to get a new alternator before installing a new coil. I’d known for a while I’d probably need to replace it soon, so it was a good time to do it. Unfortunately though, it still wouldn’t start with the new coil installed, and I didn’t have time to do any further troubleshooting. I’m planning to charge the battery up tomorrow and see if I can figure anything out.

Since my last post, I’ve checked the plug wires and found them to be good. The resistance for each one seemed to be within the acceptable range. I also changed out the ignition control module with a new Import Direct replacement and all ignition related fuses, but the car still will not start. The fusible links showed 0.00 ohms when I pulled them out and tested them, which I think means they’re fine. They don’t look burned, and I can’t feel any breaks in the wires. I’m not sure what else it could possibly be.