Autolite APP5145 Spark Plug

Autolite APP5145 Double Platinum Spark Plug

Autolite APP5145 is a Double Platinum spark plug built for stable ignition performance, easier starting, quicker throttle response, and improved fuel efficiency. It uses platinum-to-platinum firing for longer service life and consistent spark delivery in a wide range of Ford, Mercury, and Lincoln applications.

The Double Platinum Spark Plug line from Autolite focuses on OE-style form, fit, and function for domestic and import vehicles. For drivers servicing older Ford Mustang, Thunderbird, Taurus, Ranger, and related models, APP5145 provides a direct replacement option with the specifications needed for the listed applications.

Key Features

• Double platinum center and ground electrode tips for platinum-to-platinum firing
• Pre-gapped at 0.054 in. / 1.40 mm
• 14 mm thread diameter with 0.809 in. / 20.5 mm reach
• 5/8 in. hex size and tapered seat design
• Resistor spark plug with 4,000 ohm resistance
• Ceramic insulator with extra-long insulator type
• Nickel ground electrode core with a single ground electrode

Product Details

Autolite APP5145 is engineered as an OE-style replacement spark plug for vehicles that call for a tapered-seat, half-thread design. The platinum center electrode and platinum ground electrode help maintain consistent firing characteristics over time, while the resistor design supports cleaner ignition operation. This part number is commonly searched as Autolite APP5145 spark plug, Double Platinum spark plug APP5145, and Ford Mustang spark plug replacement APP5145.

Compatible With select 1983-1997 Ford Mustang, 1984-1997 Ford Thunderbird, 1984-1997 Mercury Cougar, 1988-1995 Ford Taurus, and other listed Ford, Mercury, and Lincoln models. This part cross-references Bosch 0 242 240 637 for the same application.

Common Issues This Part Can Address

• Hard starting caused by worn spark plug electrodes
• Rough idle from inconsistent spark delivery
• Reduced acceleration response from aged ignition components
• Fuel economy loss related to degraded spark plug performance
• Misfire concerns on listed Ford, Mercury, and Lincoln applications

Installation Notes and Tips

Verify the required gap and seat style before installation. APP5145 is pre-gapped at 0.054 in. / 1.40 mm, but final fitment should always match the vehicle’s OE specification for the listed application. Confirm thread diameter, reach, and terminal type before replacing plugs on Ford Mustang, Thunderbird, Taurus, Ranger, or other supported models.

Quality Assurance

Autolite supplies ignition products to the automotive aftermarket and original equipment manufacturers, with a focus on OE form, fit, and function. APP5145 is built to meet the specifications listed for the confirmed vehicle applications.