Help with the GM electronic ignition please !!

Hi, I need help because my ignition module keeps burning out after 3 or 4 months, and I don't know why. I've tried all brands, even the original one. I've read manuals, but I can't find the problem. Where should I start?
I have a Chevrolet pickup truck with a 305 engine,
carburetor,

Hi;
While I don't own an American car, perhaps my experience can help you.

Here are some tips, in no particular order (and assuming you've checked that the module connections are correct and that it has a good ground connection):

1) If your module is external, verify that it has a heat sink (an aluminum plate is sufficient in many cases). The module gets quite hot (this is normal), so it needs a good way to stay cool.

2) Check your ignition coil; make sure it's not shorted. Try installing another coil to see what happens. Check its resistance; you might need to add a ballast (external resistors, they don't cost more than S/.15).

3) NOTE: There are coils for electronic ignition and coils for condenser ignition. While they are physically identical, THEY ARE NOT THE SAME. The response time, current, load, resistance, etc., vary. High-voltage coils (MSD Blaster, Pertronix Flame Thrower, Accel, etc.) require a 0.8 Ohm ballast when used with standard modules. Most likely, you'll have to have it custom-made (converting a standard 1.6 Ohm resistor to 0.8 Ohm by cutting the wire to the appropriate length—you can calculate this using basic physics formulas).

4) Check that the distributor's pickup coil is correctly receiving the signals. The pickup coil works by magnetic induction and is located inside the distributor. Each time the shaft rotates, it sends a signal that the pickup coil detects (ON/OFF) and sends to the ignition module, which, in turn, sends the processed signal to the ignition coil to generate the spark.

5) Check your spark plug wires and the ignition coil wire. One of them might be shorted or frayed, creating unnecessary resistance.

6) Check your distributor cap and rotor: They shouldn't be cracked. The central carbon contact on the cap should be the correct size (if not, it's worn out). The contacts should still have some material remaining, and the rotor contact should be intact and clean.

7) Check your alternator: Perform maintenance (replace the relay, brushes, bearings, etc.) and verify that it's charging correctly. The alternator should never deliver more than 14V. Ideally, its output should fluctuate between 12V and 14V (depending on whether you're using the lights, audio system, fog lights, etc.).

I hope this helps.

Best of luck!

Hi, thanks for your advice.
But I have a question. My ignition coil is integrated into the distributor, and from what I've read, the external coil (the one with the ballast) is working fine. My alternator is putting out more than 15 volts. Could that be the problem? But it's burned out before, even though the alternator was fine.
How do I make a good ground connection at the module? Could you send me an example or diagram, please?

Look, buddy, your distributor is definitely high-energy. What the other guy suggested is correct, but I also suggest you use a voltmeter to measure the voltage reaching the distributor. It should be approximately the same as the battery voltage. With the ignition switch on, clean the ground or negative wire that runs from the battery to the engine. If that's okay, then replace your ignition coil. It might have an out-of-range resistance
that's affecting the ignition module. The pickup coil is unlikely to damage the module; it's more likely to stop working altogether, although not impossible. This distributor can handle 15 volts, but don't leave it like that.

ANOTHER SUGGESTION: PLACE SILICONIZED GREASE UNDER THE MODULE IF IT IS INSIDE THE DISTRIBUTOR TO DISSIPATE THE HEAT; OTHERWISE, THE MODULE WILL ROTATE QUICKLY. OK.