Autolite 2545 Spark Plug

Autolite 2545 Copper Resistor Spark Plug

Autolite 2545 is a copper resistor spark plug built for OE-style ignition performance in a wide range of Ford, Mercury, and Lincoln applications. It is engineered for quick starts, smooth acceleration, and consistent fuel economy, with the form, fit, and function expected for service replacement work.

The Copper Resistor Spark Plug line is positioned as a value-focused OE replacement option for domestic and foreign vehicles. For drivers servicing older Ford Mustang, Thunderbird, Taurus, Ranger, and related models, this plug provides a straightforward replacement path with the correct thread, reach, seat, and terminal style.

Key Features

• Autolite Copper Resistor Spark Plug, part number 2545
• Copper center electrode core with nickel tip materials
• Resistor design with 5000 ohm resistance
• Pre-gapped at 0.044 in. / 1.10 mm
• Tapered seat with 14.0 mm thread diameter and 0.809 in. / 20.5 mm reach
• Extra-long ceramic insulator for OE-style service applications
• Single ground electrode with tapered tip design
• Stud terminal type and 5/8 in. hex size

Product Details

Autolite 2545 uses a copper core center electrode to promote reliable ignition response, while the resistor design helps control electrical noise in the ignition system. The nickel-tipped electrode construction and tapered ground electrode profile support stable spark delivery in everyday driving conditions. This spark plug is a direct-fit style replacement for many older Ford Mustang, Thunderbird, Taurus, Ranger, Mercury Cougar, Mercury Sable, and Lincoln Continental applications.

This part cross-references Bosch F6DTC and DENSO Auto Parts 5048 for the same application.

Common Issues This Part Can Address

• Hard starting caused by worn or fouled spark plugs
• Rough idle from inconsistent spark delivery
• Reduced throttle response during acceleration
• Misfire symptoms related to aged ignition components
• Fuel economy loss from degraded plug performance

Installation Notes

Verify the plug gap before installation and confirm the tapered seat, 14 mm thread, 0.809 in. reach, and stud terminal match the vehicle’s OE specification. Use the fitment notes for model-specific details, especially on applications where OE half-thread designs were replaced by full-thread designs. Autolite 2545 fits 1987-1990 Ford Mustang, 1994-1997 Ford Mustang, and 1985-1988 Ford Ranger among many other listed Ford, Mercury, and Lincoln vehicles.

• Fits 1994-1997 Ford Mustang, N/A
• Fits 1996-1997 Ford Thunderbird, N/A
• Fits 1993-1997 Mercury Cougar, N/A
• Fits 1993-1995 Ford Taurus, N/A
• Fits 1992-1995 Ford Thunderbird, N/A
• Fits 1995 Ford Windstar, N/A
• Fits 1993-1995 Mercury Sable, N/A
• Fits 1988-1994 Lincoln Continental, N/A
• Fits 1988-1992 Ford Taurus, N/A
• Fits 1988-1992 Mercury Cougar, N/A
• Fits 1988-1992 Mercury Sable, N/A
• Fits 1987-1991 Ford LTD Crown Victoria, N/A
• Fits 1989-1991 Ford Thunderbird, N/A
• Fits 1987-1991 Mercury Colony Park, N/A
• Fits 1986-1991 Mercury Grand Marquis, N/A
• Fits 1987-1990 Ford Mustang, N/A
• Fits 1986-1990 Lincoln Town Car, N/A
• Fits 1985-1988 Ford Ranger, N/A
• Fits 1986-1988 Ford Thunderbird, N/A
• Fits 1988 Ford Thunderbird, N/A
• Fits 1986-1988 Mercury Cougar, N/A
• Fits 1986-1987 Ford Aerostar, N/A
• Fits 1986-1987 Lincoln Continental, N/A
• Fits 1986-1987 Lincoln Mark VII, N/A
• Fits 1986 Ford LTD, N/A
• Fits 1986 Ford Mustang, N/A
• Fits 1986 Mercury Capri, N/A
• Fits 1985-1986 Mercury Capri, N/A
• Fits 1984-1986 Mercury Marquis, N/A
• Fits 1983-1985 Ford LTD, N/A
• Fits 1984 Ford Ranger, N/A
• Fits 1983-1984 Mercury Capri, N/A
• Fits 1983 Ford Fairmont, N/A
• Fits 1983 Ford Ranger, N/A
• Fits 1983 Mercury Marquis, N/A
• Fits 1983 Mercury Zephyr, N/A

Quality Assurance

Autolite supplies ignition products to the automotive aftermarket and original equipment manufacturers, and this spark plug is built to OE form, fit, and function standards for service replacement use.