Autolite 847 Spark Plug

Overview of Autolite Copper Resistor Spark Plug 847

The Autolite Copper Resistor Spark Plug 847 is engineered to deliver reliable ignition performance for select Buick, Cadillac, Oldsmobile, and Pontiac vehicles. Designed with a copper core and resistor technology, this spark plug supports efficient combustion and reduces electrical interference.

• Resistance: 5000 ohms for noise suppression
• Center electrode core made of copper with nickel tip
• Tapered ground electrode tip constructed from nickel
• Stud-type electrical terminal for secure connection
• Pre-gap size options: 0.070 inch and 1.80 mm
• Flat seat type with 14.0 mm thread diameter and 0.374 inch (9.5 mm) reach
• Hex size: 13/16 inch (21 mm) for installation
• Ceramic mid-projection insulator for durability
• Single ground electrode design

About the Copper Resistor Spark Plug Product Line

The Autolite Copper Resistor Spark Plug line combines copper core electrodes with resistor technology to minimize radio frequency interference while maintaining strong spark energy. This product line is designed to meet the ignition requirements of various GM vehicles, including models from Buick, Cadillac, Oldsmobile, and Pontiac. The resistor feature helps protect sensitive electronic components in modern ignition systems.

Detailed Product Description

The Autolite Copper Resistor Spark Plug 847 features a copper center electrode core that enhances thermal conductivity and improves spark efficiency. The nickel ground electrode with a tapered tip design ensures consistent spark gap and durability under high temperatures. The resistor type spark plug with 5000 ohms resistance reduces electromagnetic interference, which is critical for vehicles equipped with advanced electronics. The ceramic mid-projection insulator provides excellent insulation and heat resistance, while the flat seat and precise thread diameter ensure proper fitment and sealing in the combustion chamber.

Compatible Vehicles and Applications

• Buick models including Century, LeSabre, Regal, Skylark, and more
• Cadillac models such as Eldorado, Seville, and DeVille
• Oldsmobile models including Cutlass, Delta 88, and 98
• Pontiac models like Firebird, Grand Prix, and Bonneville

This spark plug is suitable for secondary ignition systems in these vehicles, providing stable ignition performance and helping to maintain engine efficiency.

Common Issues Addressed by Autolite Spark Plug 847

• Misfires caused by worn or fouled spark plugs
• Radio frequency interference affecting vehicle electronics
• Poor fuel combustion leading to reduced engine performance
• Ignition system noise impacting sensitive onboard systems
• Inconsistent spark gap resulting in rough idling or hesitation

Installation Notes and Tips

Ensure the spark plug gap matches the vehicle manufacturer’s specifications before installation. Use a torque wrench to tighten the spark plug to the recommended torque to avoid damage to the threads or improper sealing. The 13/16 inch (21 mm) hex size allows for standard spark plug socket compatibility. Inspect the ignition system components for wear or damage during replacement to maintain optimal performance.

Quality Assurance and Warranty

Autolite spark plugs are manufactured to meet OEM standards for fit, form, and function. The Copper Resistor Spark Plug 847 undergoes rigorous quality control to ensure durability and consistent performance. While specific warranty details may vary, Autolite products typically come with a limited warranty against manufacturing defects.