Topic: Need weak spark help
in Forum: C3 Engines
The engine of my '81 feels like it has a skip. I started removing the plug wires from the cap one by one while it was running to notice a difference in how it ran. When I got to No. 8 it didn't feel like it ran any different while the others were noticable. I changed the wire and got the same results. It has new plugs and they are all gapped properly. When I put a screwdriver in and grounded the wire to get it to arc, I got a faint orange spark. In fact when I compared it to No. 6, that spark didn't look too much stronger. Could I have a bad coil? Rotor? Cap? Combo? Other? Any help would be appreciated. Thanks, George
Lifetime MemberModerator
HEIs are bad about arcing on the bottom side of the rotor, so check it carefully. If you see anything that looks like lightning bolt traces on the bottom side of the rotor(or the cap), it is bad, and needs to be replaced.
The terminal for #8 on the cap may be corroded, also.
You'll probably wind up replacing the Ignition module to solve the problem. They don't like heat, or mis-fires. If you have a bad wire, or plug, or cross-firing in the cap, it will eventually damage the module.
Check the cap and rotor first, and replace if needed.
Joel Adams
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