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Sparks are flying

my coil is sparking in my distrubtor cap and I am replaced the cap rotor and coil what do I do now???

Not sure what you mean. Normally there will be some sparks as the rotor goes around and touches the contact points. Is it cross-firing to the wrong spot? How do you know, can you see it? Are you sure there’s no moisture or other contamination under the cap?

What kind of vehicle?


the coil sits on top of the cap and the coil is arching to its self

86 cutlass with the 307

The problem might be with the ignition module in the distributor.

Ignition modules function in two modes. These are the start and run modes. When starting the engine the module allows full battery to the coil. Once the engine starts, the module drops the voltage to the coil. If the module has failed where it’s not switching to the run mode and is supplying full battery voltage while the engine’s running, sparks will fly.


how often do those go bad because I replaced everything but the condensor about 2 months ago

There actually is a part on this system called a condensor and sometimes it gets replaced? Condensor=points system, whats going on here?

If you disconnect a spark plug wire from the spark plug, and intend to crank the engine, you MUST provide a ground for the spark, or, disconnect the small (primary) coil (power) wire so that a spark isn’t built up. If you don’t, and the coil is energised and builds up a spark, the spark WILL find a way to discharge. It will discharge through the coil, itself, burning a path to ground through the coil.

I don’t think there is anything called a condenser in that system. That is one of the old GM HEI systems and those are notorious for being able to generate very high voltages if they cannot fire the plug normally. If the electricity cannot get to the spark plug, it will just keep building until it can burn through somewhere and arc to ground.

Usually, the first component to get burned through is the rotor. Look for discolorations in the plastic around the metal strip on top of the rotor.

Replace your spark plug wires if they are several years old. May as well replace the plugs while you are at it. You may have a bad plug.

Then, whatever components you are seeing the spark jump through really should be replaced again as there is now a microscopic hole in the plastic with a carbon trace through it, so it is an easy path for future arcing. I’m guessing that this would be the coil in your case.