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Q: 86 GMC 305 quits firing occasionally

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I have an '86 GMC 305. It quits firing from time to time. I replaced the coil, control module, rotor and pick-up coil. Do you have any thoughts what could cause this?

This car is very old. Personally, I’d just go and get a rebuilt distributor. Most companies sell the rebuilt distributors with the lifetime warranty. They don’t cost that much. Replace your entire distributor assembly.

If that doesn’t fix it, then you’re going to have to trace the wiring all through and see where the wiring short is. You changed that control module and the coil, but I would change the entire distributor assembly. There’s so many tiny wires there that can short out and they are so cheap. Just change the entire distributor assembly with a rebuilt unit to have this issue taken care of.

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