Autolite 104 Spark Plug

Reliable Ignition with Autolite Copper Resistor Spark Plug 104

The Autolite Copper Resistor Spark Plug 104 delivers consistent ignition performance for a wide range of vehicles including Buick, Ford, Chevrolet, and Mercedes-Benz models. Designed with durable copper electrodes and a tapered ground electrode tip, this spark plug supports efficient combustion and engine reliability.

• Resistance: 5000 ohms for effective electrical noise suppression
• Ground Electrode Tip Design: Tapered for precise spark delivery
• Center and Ground Electrode Material: Copper for optimal conductivity
• Pre-Gap Size: Factory set at 0.050 inches (1.30 mm) for proper spark gap
• Hex Size: 5/8 inch (16 mm) for standard installation tools
• Seat Type: Tapered for secure fit and sealing
• Insulator Material: Ceramic with mid projection design for heat resistance
• Electrical Terminal Type: Stud for reliable connection

About the Autolite Copper Resistor Spark Plug Line

The Copper Resistor Spark Plug line from Autolite is engineered to reduce radio frequency interference while maintaining strong ignition performance. Featuring a 5000 ohm resistor, these plugs help protect sensitive electronic components in modern vehicles. The copper core electrodes enhance heat dissipation and conductivity, making them suitable for a variety of secondary ignition systems.

Technical Details and Compatibility

The Autolite 104 spark plug features a single tapered ground electrode made of copper and nickel core material, paired with a copper center electrode. The pre-set gap of 0.050 inches (1.30 mm) ensures optimal spark efficiency. With a thread diameter of 14.0 mm and a reach of 0.679 inches (17.0 mm), this spark plug fits many domestic and import vehicles. Compatible makes include Buick, Cadillac, Chevrolet, Ford, GMC, Isuzu, Lincoln, Mazda, Mercedes-Benz, Mercury, Oldsmobile, and Pontiac. Models such as the Ford F-150, Chevrolet Camaro, Buick Century, and Mercedes-Benz 300E are among those supported by this part number 104.

Common Applications and Problem Solving

• Restores proper ignition timing and spark delivery
• Reduces engine misfires and rough idling
• Minimizes radio frequency interference affecting vehicle electronics
• Improves fuel efficiency by ensuring complete combustion
• Prevents fouling and electrode wear in older ignition systems

Installation Notes and Tips

Before installation, verify the spark plug gap is set to the manufacturer’s specifications, which for this plug is 0.050 inches (1.30 mm). Use a 5/8 inch (16 mm) socket wrench for removal and installation. Apply anti-seize compound sparingly on the threads to prevent galling, but avoid contaminating the electrode area. Torque the spark plug to the vehicle manufacturer’s recommended specification to ensure proper sealing and performance.

Quality Assurance and Warranty

Autolite Copper Resistor Spark Plug 104 is manufactured to meet or exceed OEM standards for ignition components. The use of ceramic insulators and copper electrodes ensures durability under high temperature and pressure conditions. While specific warranty details vary by distributor, Autolite products typically come with a limited warranty against manufacturing defects. Consult your vehicle service manual and local regulations for proper maintenance intervals and replacement guidelines.