Autolite APP3923 Spark Plug

Autolite APP3923 Double Platinum Spark Plug

Autolite APP3923 is a Double Platinum spark plug built for OE-style fit, form, and function across a wide range of import and domestic applications. It uses platinum-to-platinum firing for longer service life and consistent ignition performance, with easier starts, quicker throttle response, and improved fuel efficiency.

For drivers servicing vehicles such as the Audi A4, Volkswagen Jetta, or Mercedes-Benz S65 AMG, this plug provides a direct replacement option with the correct reach, thread size, seat type, and pre-gap specification for listed applications.

Key Features

• Double platinum firing design for extended plug life
• Platinum center and ground electrode tips
• Pre-gapped at 0.044 in. / 1.10 mm
• Resistor spark plug with 4,000 ohm resistance
• Flat seat, 14 mm thread diameter, 5/8 in. hex
• Ceramic insulator with mid-projection design
• OE-style replacement for many foreign and domestic vehicles

Product Details

Autolite Double Platinum Spark Plugs are engineered as an OE-style replacement for a broad range of applications, including Audi A4, Volkswagen Tiguan, Mitsubishi Outlander Sport, and Mercedes-Benz Maybach S600 models. The platinum-to-platinum firing design helps maintain stable spark performance over time, while the resistor construction supports ignition system noise control. Part number APP3923 is also cross-referenced to Anchor 3113 for the same application.

Built with a 14 mm thread, 0.750 in. reach, flat seat, and stud terminal, APP3923 is specified for many vehicles that call for a 0.044 in. gap, including several Mitsubishi, Toyota, Honda, and Volkswagen platforms. Always verify the exact engine and gap requirement against the vehicle listing before installation.

Common Problems This Part Addresses

• Hard starting or extended crank time
• Rough idle caused by worn spark plugs
• Reduced acceleration response
• Declining fuel economy from aged ignition components
• Misfire concerns related to plug wear

Installation Notes and Tips

• Confirm vehicle-specific fitment before installation, especially on applications that require two plugs per cylinder.
• Check the listed gap requirement for your exact vehicle; some applications use a different preset gap than the plug’s 0.044 in. specification.
• Use the correct torque procedure for the cylinder head material and plug seat type.
• Inspect ignition coils, boots, and wires during service to avoid repeat misfire issues.

Quality Assurance

Autolite supplies ignition products to the automotive aftermarket and original equipment manufacturers, and APP3923 is built to OE-style standards for listed applications. Part number APP3923 is a practical replacement choice for drivers maintaining factory-style ignition performance.