Spark Plug Cable

Spark Plug cables are sometimes referred to as secondary ignition wires. The wires transfer electrical current from electronic ignition coils to individual spark plug at each cylinder. The nonmetallic spark plug cables have built in resistance. The cables provide suppression of radio frequency emissions from ignition system.

Check spark plug cable connections for good contact at coil or coil pack and distributor cap towers and at spark plugs. Terminals should be fully seated. The nipples and spark plug covers should be in good condition. Nipples should fit tightly on coil or coil pack and distributor cap towers and spark plug cover should fit tight around spark plug insulators. Loose cable connections can cause ignition malfunctions by permitting water to enter towers, corroding, and increasing resistance. To maintain proper sealing at terminal connections, connections should not be broken unless testing indicates high resistance, an open circuit or other damage.

Clean high tension cables with a cloth moistened with a non-flammable solvent and wipe dry. Check for brittle or cracked insulation. Plastic clips in various locations protect cables from damage. When cables are replaced, clips must be used to prevent damage to cables.