Rick's Free Auto Repair Advice

Double fine wire electrode spark plug — Why it’s better

Why carmakers are switching to double fine wire electrode spark plugs

A double fine wire electrode spark plug (DFE) is built on a traditional copper core with a fine wire fused to the core. A precious metal disc is fused to the bottom of the center electrode fine wire and a second fine wire with precious metal tip is fused to the side ground strap.

comparison of double fine wire electrode spark plug versus traditional nickel spark plug

Advantages of a double fine wire ((DFE) spark plug

The much small diameter center electrode requires much lower voltage to jump the gap. The smaller electrode, because it has far less mass also reduces flame quenching. So a double fine wire electrode spark plug provides better ignitability which translates into more power and increased fuel economy.

The precious metal disc on the bottom of the center electrode and on the side electrode resist gap erosion and maintain their sharp edge much longer than a traditional nickel fused center electrode. So they last longer than traditional nickel fused center electrode spark plugs.

Spark plug manufacturers use either platinum or iridium for the precious metal tips.

WARNING: Never use a “coin gap gauge” when checking the gap on a double fine wire spark plug. The wedge can break off the fine wire electrode. Always use a wire style gauge to check or adjust the gap.

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Posted on by Rick Muscoplat



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