The uneven running of car engine because of fouled, carbon gapped spark plug ,is easily corrected by pulling off plug wire boot and holding close, so as spark jumps to plug. The RPM returns to even smooth running. This wide IN SERIES spark gap causes ignition coil to clear that cylinder. Does this mean that the cylinder NOW IS GETTING a higher killovolts , and is a method to increase high voltage? Gadgets on the market way back in time connected between distributor cap and plug wire, and sold to the public as a new "gas saver". (In line accessory spark gap)

 

With modern engine fuel injection and unleaded fuel, fouled plugs are mostly something in the past.

 

Yes it does mean that the Coil-Voltage will go higher,
possibly high enough to damage the Coil.

"Spark-Plug-Anti-Foulers" are a superior solution to fouling Spark-Plugs in a worn-out, Oil-Burning-Engine.
( aside from re-building the Engine of course )
They work by making the Spark-Plugs operate at much higher Temperatures,
by way of moving the Spark-Plugs further away from the Cylinder-Head, where they are normally cooled by the Water-Jacket.

Run ~50-weight or heavier Oil to slow down the Oil burning.
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