Autolite 5144 Spark Plug

Autolite 5144 Copper Resistor Spark Plug

Autolite 5144 is a copper resistor spark plug built for OE-style service in a wide range of Ford, Mercury, and Mazda applications. It is engineered for quick starts, smooth acceleration, and consistent ignition performance, with a 0.054 in. (1.40 mm) pre-gap on most listed applications.

Key Features

• Copper center electrode for reliable spark transfer and responsive ignition
• Nickel center and ground electrode tip materials for standard wear characteristics
• Resistor design with 4,000 ohms resistance to help reduce electrical noise
• Extra-long ceramic insulator for stable heat control and durability
• Tapered seat, 14.0 mm thread diameter, and 5/8 in. hex size
• OE-style form, fit, and function for maintenance replacement service

Product Details

The Autolite Copper Resistor Spark Plug line is focused on dependable everyday ignition performance for foreign and domestic vehicles. Part number 5144 uses a standard/regular center electrode design, a single ground electrode, and a stud terminal type. Its tapered ground electrode tip design and nickel electrode materials support consistent firing characteristics in routine tune-up service. This part cross-references 43 and AGSF34C for the same application.

Compatible With long-tail applications such as 2008 Ford F-150 spark plug replacement, 2006-2008 Ford Ranger ignition service, and 2001-2007 Mazda B4000 tune-up maintenance. It also covers additional Ford F-150, Ford Focus, Ford Freestar, Ford Escort, Mercury Tracer, Ford E-Series vans, and related applications listed in the fitment data. Autolite 5144 is a practical OE-style choice when replacing worn spark plugs in Ford F-150 and Ranger engines that call for this specification.

Common Issues This Part Can Address

• Hard starting caused by worn or fouled spark plugs
• Rough idle from inconsistent ignition firing
• Reduced throttle response during acceleration
• Misfire symptoms related to plug wear or gap drift
• Electrical interference concerns in resistor-equipped ignition systems

Installation Notes and Tips

Verify the required gap before installation, since listed applications call for 0.054 in. (1.4 mm), 0.044 in. (1.1 mm), 0.050 in. (1.3 mm), or 0.052 in. (1.3 mm) depending on year and model. Confirm the vehicle-specific service specification for your Ford F-150, Ford Ranger, or Mazda B4000 before installing Autolite 5144. Use the correct torque procedure for tapered-seat spark plugs and inspect ignition wires or coils during service.

Quality Assurance

Autolite supplies ignition products to the automotive aftermarket and original equipment manufacturers, with a focus on OE-style replacement fit and function. Part number 5144 is built to meet standard spark plug service requirements for the listed applications.