Name: Copper Plus Spark Plug: Dependable Performance, OE Replacement, RS12YC
Brand: Champion
SKU: 401
Price: 2.99 USD
Rating: 4.5 (51 reviews)

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$2.99

Dependable Performance, OE Replacement, RS12YC. This Champion® spark plug features a copper core electrode that provides increased conductivity and heat control for good overall wear. The Copper Plus design ensures dependable performance and durability, while the copper core center electrode allows for accurate control of heat range, extending the spark plug’s life. Built to ISO and SAE standards, it offers superior corrosion resistance and proven performance. The nickel center electrode tip and tapered seat type further enhance its reliability, making it an excellent choice for maintaining your engine’s efficiency.

Product Features:

Copper Plus – Dependable Performance and Durability
Copper core center electrode allows for accurate control of heat range for longer life
Superior corrosion resistance
Built to ISO and SAE standards for proven performance
Built to ISO and SAE standards for proven performance
Enhanced Conductivity and Heat Control: The Champion Copper Plus Spark Plug features a copper core electrode that provides increased conductivity and heat control, ensuring good overall wear and extending the spark plug’s life.
Reliable Nickel Center Electrode Tip: Featuring a nickel center electrode tip and a tapered seat type, this spark plug enhances reliability and ensures optimal engine performance.

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$5.79

Twin-Tip design enables faster flame propagation for more complete combustion.

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$48.49

ACCEL HP Spark Plugs are made with a Copper core which is a better conductor than Platinum and Iridium. They deliver a stronger spark especially in high performance applications where high combustion pressures are present. Copper is much better at dissipating heat than other materials which lessens the chance of a misfire. ACCEL HP Spark Plugs are gapable allowing you to open the gap exposing a larger flame kernel or close it if needed for high boost applications. All ACCEL HP Spark Plugs have machine rolled threads allowing for a more precise thread engagement and torque retention.

Product Features:

The Copper core is a better conductor than Iridium or Platinum plugs
Copper dissipates heat much better than other materials
C
Unlike Iridium or Platinum plugs, the ACCEL HP plugs are gapable
Machine rolled threads for precise thread engagement
Stock heat range
Whether using on the street or on the strip, ACCEL HP Copper Core spark plugs deliver!

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$7.99

Manufactured to the strictest OE performance, durability and emissions standards.

Product Features:

OE grade platinum on both center and ground electrodes
Premium shell construction with machine-rolled threads
Superior thermal conductivity
Sustained spark performance over 60,000 miles
Reduced secondary required voltage, increased ignition efficiency
Satisfied customers, reduced shop comebacks
Double Platinum

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$9.35

The NGK Standard copper core spark plug provides OEM quality, consistent performance and extended long life.

Product Features:

Trivalent Metal Plating Provides Superior Anti-Corrosion and Anti-Seizing Properties
Corrugated Ribs Prevent Flashover
Pure Alumina Silicate Ceramic Insulator, Provides Superior Strength and Better Heat Transfer
Copper Core Aids in Heat Removal
Triple Seals Prevent Leakage

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$9.99

This spark plug non fouler is designed for easy installation on specified vehicles to protect spark plugs from fouling and damage. It is engineered for durability and reliable performance.

Product Features:

Direct replacement – this spark plug non fouler is designed for easy installation to protect spark plugs from fouling and damage on specified vehicles
Ideal solution – this non-fouler preserves spark plug life and is a reliable replacement for an original non-fouler that has failed due to corrosion
Durable construction – made from quality components to ensure reliable performance and a long service life
Trustworthy quality – backed by team of product experts in the United States and more than a century of automotive experience

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$3.49

Dependable performance. This Champion® spark plug features a copper core electrode that provides increased conductivity and heat control for good overall wear.

Product Features:

Copper Plus – Dependable Performance and Durability
Copper core center electrode allows for accurate control of heat range for longer life
Superior corrosion resistance
Built to ISO and SAE standards for proven performance
Built to ISO and SAE standards for proven performance

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$3.54

Motorcraft Original Equipment Copper Core spark plugs are designed, engineered and recommended by Ford Motor Company.

Product Features:

Same part installed when the engine rolled off the assembly line
Designed to deliver quick starts, enhanced fuel economy and smooth acceleration

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$4.49

With over 100 years of engineering expertise and more than 11 billion plugs sold, Autolite continues to lead the industry. Designed and engineered in the USA, these spark plugs feature a high nickel alloy side electrode that maintains a precise gap, and a full platinum tip that ensures virtually no gap erosion for extended life. The necked-down center electrode fires quicker and cleaner with less voltage, resulting in easier starts, quicker acceleration, and improved fuel economy compared to standard plugs. The tapered seat type further enhances performance and durability.

Product Features:

High nickel alloy side electrode maintains precise gap
Full platinum tip assures virtually no gap erosion for long life
Necked-down center electrode fires quicker, cleaner with less voltage for easier starts, quicker acceleration and improved fuel economy (as compared to standard plugs)
Tapered Seat Type: Enhances performance and durability for a reliable driving experience.

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$4.79

Autolite has over 100 years of engineering experience and has sold over 11 billion plugs. Designed and engineered in the USA, Autolite Platinum spark plugs provide a center wire platinum firing tip which provides reduced gap erosion, fewer misfires, better performance and increased durability. Consider upgrading to Autolite Double Platinum or Iridium XP spark plugs for increased performance.

Product Features:

High nickel alloy side electrode maintains precise gap
Full platinum tip assures virtually no gap erosion for long life
Necked-down center electrode fires quicker, cleaner with less voltage for easier starts, quicker acceleration and improved fuel economy (as compared to standard plugs)

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$8.99

Autolite® Iridium XP Enhanced Alloy Technology Spark Plugs is one of the brand’s most technologically advanced spark plugs ever. These spark plugs provide better durability and a more focused ignition for better overall ignitability and optimum performance. Autolite® spark plugs are the best alternativ e to OE spark plugs, offering OE form, fit and function for all makes and models, both foreign and domestic, at a value price. Autolite provides the automotive aftermarket and original equipment manufacturers with the highest quality ignition products and is the leading supplier of spark plugs.

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$8.49

Champion® Iridium – the ultimate element. This spark plug’s fine-wire iridium center and platinum ground electrodes provide the sharpest spark focus for maximum performance.

Product Features:

Champion Iridium – Maximum Performance. Premium Spark Plug
Iridium center electrode delivers maximum life
Fine-wire center electrode and V-trimmed for greater ignitability
V-trimmed ground electrode promotes sharper spark focus
Maintains stable operating temperature under all engine loads
Heat-Active┐ alloy allows electrodes to reach optimal temperature quickly

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$6.49

Engineered for superior ignition performance, the Motorcraft High-Performance Spark Plug is designed to optimize fuel efficiency and ensure reliable starts. Crafted with precision, this spark plug offers exceptional durability and consistent performance, making it an ideal choice for maintaining your vehicle’s peak performance. Trust Motorcraft for quality and dependability in every drive.

Product Features:

Enhances Fuel Efficiency: Designed to optimize fuel consumption, ensuring you get the most out of every gallon.
Superior Ignition Performance: Engineered for reliable starts and consistent performance, providing peace of mind on every drive.
Exceptional Durability: Crafted with precision to withstand the demands of high-performance engines, ensuring long-lasting use.
Consistent Performance: Maintains your vehicle’s peak performance, making it an ideal choice for regular maintenance.
Quality and Dependability: Trust Motorcraft for high-quality spark plugs that deliver dependable performance in every drive.
Enhances Fuel Efficiency: Designed to optimize fuel consumption, ensuring you get the most out of every gallon.
Superior Ignition Performance: Engineered for reliable starts and consistent performance, providing peace of mind on every drive.
Exceptional Durability: Crafted with precision to withstand the demands of high-performance engines, ensuring long-lasting use.
Consistent Performance: Maintains your vehicle’s peak performance, making it an ideal choice for regular maintenance.
Quality and Dependability: Trust Motorcraft for high-quality spark plugs that deliver dependable performance in every drive.

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$6.42

2X longer service life compared to standard copper plugs Bosch Platinum Spark Plugs are the newest member of our OE fine wire spark plug family. From the brand trusted in the world’s most advanced engines, Bosch Platinum Spark Plugs are engineered to provide you with improved ignitability and performance.

Product Features:

OE design for optimum fit and function
Fine wire design delivers improved ignitability and performance life
Center electrode is an ultra fine wire design.
Copper core provides broader heat range to resist pre-ignition
Tapered shape ground electrode reduces flame shrouding for improved combustion
Yttrium enhanced to resist wear
Nickel-plated shell with rolled threads
Ribbed insulator design

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$6.99

The Spark Plugs are the product of years of fundamental research in the combustion field. The unique patented electrode configuration of these new The spark plugs increases the amount of combustion pressure created during each power stroke of an engine, which results in a marked increase in power output, fuel economy, and reduced emissions in all gasoline engines. E3.44 is a 14mm, 0.708 reach plug with a taper seat. It fits domestic applications from the mid-90s. The automotive plugs have three legs securing the Diamond FIRE electrode to the shell. This allows for excellent heat transfer, and helps to create more turbulence in the cylinder. The patented Diamond FIRE side wire is proven to increase power, reduce fuel consumption and improve hydrocarbon emissions in long-term use.

Product Features:

E3’s Diamond Fire edge to edge ground electrode provides maximum performance with increased efficiency and a faster more complete burn.
Smoother Acceleration & Idle – The faster flame initiated by the The spark plug results in a more complete burn of the ingested fuel charge. More pressure is created against the piston more fuel is put to work
Energy – Power output improved up to 6% on average in the typical operating ranges. Results will vary.
Efficiency – The “diamond shaped” side wire electrode projects the combustion spark in a way that more quickly ignites the air/fuel mixture, thereby creating a significantly faster and larger flame kernel. The result is that more fuel is put to work durin
E3’s patented Diamond Fire Technology provides a cleaner burning combustion, which translates into fuel savings and reduced engine carbon deposits
The Spark Plugs are pre-gapped at the factory and cannot be adjusted.
Patented Electrode Configuration: The unique patented electrode design of the E3.44 spark plugs increases combustion pressure, resulting in enhanced power output and improved fuel economy.
Superior Heat Transfer: The three-leg design securing the Diamond FIRE electrode to the shell ensures excellent heat transfer and creates more turbulence in the cylinder for optimal performance.
Compatibility: The E3.44 spark plug is a 14mm, 0.708 reach plug with a taper seat, fitting domestic applications from the mid-90s.
Environmental Benefits: By improving combustion efficiency, these spark plugs help reduce emissions, contributing to a cleaner environment.

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$3.49

Autolite has over 100 years of engineering experience and has sold over 11 billion plugs. Guaranteed to deliver quick starts, good fuel economy and smooth acceleration, Autolite Copper Core spark plugs are designed to meet or exceed OES design requirements. Consider upgrading to Autolite Platinum, Double Platinum or Iridium XP plugs for improved engine performance. Copper core plugs are the industry standard.

Product Features:

Copper-glass seal bonds insulator, terminal post center electrode together; assures full required voltage at spark gap; gas-tight seal (100% leak proof)
Multi-rib insulator reduces danger of “flash-over”
One-piece terminal post adds strength
Resistor reduces radio frequency interference (RFI) and electrode erosion

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$9.79

ACDelco GM Original Equipment Double Platinum Spark Plugs are designed, engineered, and tested to rigorous standards, and are backed by General Motors. With a copper core and double platinum pads on the center electrode, these plugs are designed to deliver long-lasting performance. ACDelco GM Original Equipment parts are the true OE parts installed during the production or validated by General Motors for GM vehicles. Some ACDelco GM Original Equipment parts may have formerly appeared as GM Genuine Parts (OE) or ACDelco Professional.

Product Features:

One-piece, fired-in suppressor seal blends three glass types for a gas-tight seal that helps reduce radio frequency and engine interference, regulate spark plug energy, and protect against compression pressures for long life
Double platinum point pad on center and ground electrode offer excellent durability and consistent voltage demands to help reduce wear on ignition system
Some ACDelco GM Original Equipment parts may have formerly appeared as GM Genuine Parts (OE) or ACDelco Professional
ACDelco GM Original Equipment parts are designed, engineered and tested to rigorous standards, and are backed by General Motors
GM Engineers design and validate OE parts specifically for your Chevrolet, Buick, GMC, or Cadillac vehicle
GM regularly updates production and service part designs to integrate new materials and technologies
Copper Core: Designed with a copper core to provide better heat transfer and improved conductivity.
Conical Seat Type: Equipped with a conical seat type for a secure fit and optimal performance.
Resistor Type: Includes a resistor to help reduce radio frequency interference, ensuring smoother engine operation.

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$5.49

Motorcraft Spark Plugs are original equipment on Ford Motor Company vehicles, engineered to meet strict Ford engineering standards for performance and reliability. These spark plugs are matched to specific engines to provide enhanced durability, eliminate misfires, reduce fuel consumption, and optimize emissions. With a platinum center and ground electrode tip, they are resistant to oxidation and arc erosion, ensuring long-lasting performance. The multi-rib insulator protects against misfires, and they are designed to fit Ford, Lincoln, and Mercury vehicles exactly. Backed by Motorcraft’s Service Parts Warranty, these spark plugs offer service intervals of up to 100,000 miles and help prevent false check engine lights. Made with high-quality materials, Motorcraft Spark Plugs deliver reliable performance for almost any application, making them the same trusted components that were in your vehicle when it was manufactured.

Product Features:

Motorcraft spark plugs are matched to specific engines to provide enhanced durability, eliminate misfires, reduce fuel consumption and optimize emissions.
Backed by Motorcraft’s Service Parts Warranty
Exact fit for Ford, Lincoln and Mercury vehicles
Resistant to oxidation and arc erosion.
Multi-rib insulator protects against misfire.
Service intervals of up to 100,000 miles.
Motorcraft Spark Plugs are designed with high quality materials to provide reliable performance for almost any application.
Motorcraft Spark Plugs are what was in the vehicle when it was manufactured
Motorcraft ignition components help prevent false check engine lights.
Enhanced Durability: Engineered with a platinum center and ground electrode tip, these spark plugs are resistant to oxidation and arc erosion, ensuring long-lasting performance.
Fuel Efficiency and Emissions: Designed to reduce fuel consumption and optimize emissions, contributing to a more efficient and environmentally friendly driving experience.

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$5.29

The Motorcraft Spark Plug is a high-quality replacement spark plug designed to provide reliable performance and long-lasting durability for your vehicle. It features a nickel alloy electrode that provides superior wear resistance and a platinum tip that ensures consistent performance over the life of the plug. The Motorcraft Spark Plug also has a ribbed insulator design that helps prevent misfires and a copper core that provides efficient heat transfer. It is designed to meet or exceed OEM specifications and is compatible with a wide range of vehicles. Whether you’re looking to replace worn-out spark plugs or upgrade to a higher-quality option, the Motorcraft Spark Plug is an excellent choice that will help keep your engine running smoothly and efficiently.

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$8.99

Our best spark plug! Autolite has over 100 years of engineering experience and has sold over 11 billion plugs. Designed and engineered in the USA, the Autolite Iridium XP spark plugs feature an iridium-enhanced 0.6mm finewire design and patented platinum sidewire technology to provide better overall durability and a more focused ignition for enhanced ignitability and performance. Features double Iridium-enhanced alloy technology center electrode for improved durability and wear resistance.

Product Features:

0.6 mm finewire design improves ignitability
Patented V-trimmed platinum sidewire technology resists wear
OE equivalent design is engineered for every engine
Designed for better overall durability with virtually no gap erosion

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$5.99

Twin-Tip design enables faster flame propagation for more complete combustion.

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$2.99

Autolite has over 100 years of engineering experience and has sold over 11 billion plugs. Guaranteed to deliver quick starts, good fuel economy and smooth acceleration, Autolite Copper Core spark plugs are designed to meet or exceed OES design requirements. Consider upgrading to Autolite Platinum, Double Platinum or Iridium XP plugs for improved engine performance. Copper core plugs are the industry standard.

Product Features:

Copper-glass seal bonds insulator, terminal post center electrode together; assures full required voltage at spark gap; gas-tight seal (100% leak proof)
Multi-rib insulator reduces danger of “flash-over”
One-piece terminal post adds strength
Resistor reduces radio frequency interference (RFI) and electrode erosion

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$5.99

Autolite has over 100 years of engineering experience and has sold over 11 billion plugs. Designed and engineered in the USA, Autolite Double Platinum spark plugs feature platinum-to-platinum firing which virtually eliminates gap erosion, reduces misfires and increases durability of the plug. Consider upgrading to Autolite Iridium XP spark plugs for increased performance.

Product Features:

Works to optimize engine performance for a longer life and improved fuel economy
OE design
Full-platinum tips; platinum on both the center and side electrodes to promote reduced gap wear
Platinum ball welding process provides a consistent point of contact for enhanced adhesion

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$4.79

Autolite has over 100 years of engineering experience and has sold over 11 billion plugs. Designed and engineered in the USA, Autolite Platinum spark plugs provide a center wire platinum firing tip which provides reduced gap erosion, fewer misfires, better performance and increased durability. Consider upgrading to Autolite Double Platinum or Iridium XP spark plugs for increased performance.

Product Features:

High nickel alloy side electrode maintains precise gap
Full platinum tip assures virtually no gap erosion for long life
Necked-down center electrode fires quicker, cleaner with less voltage for easier starts, quicker acceleration and improved fuel economy (as compared to standard plugs)

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$4.99

NGK V-Power spark plugs offer reliable performance and improved ignitability over standard nickel plugs. Engineered specifically for OE applications, the special V-cut nickel alloy center electrode and concave ground electrode of NGK’s V-Power spark plug increases ignitability providing quicker starts and smoother idle. NGK’s legendary high grade alumina silicate ceramic creates a stronger insulator for optimal dielectric performance. Trivalent metal plating ensures superior anti-corrosion and anti-seizing properties.

Product Features:

ACTUAL OE or EQUIVALENT DESIGN: OEM quality construction nickel alloy center electrode with V-groove provides consistent performance
RECOMMENDED USAGE: Best for vehicles with OE nickel alloy plugs, not recommended on vehicles with factory precious metal plugs
NGK’s OE CERAMIC TECHNOLOGY: High grade alumina silicate ceramic creates a stronger insulator for optimal dielectric performance
SOLID COPPER CORE: 98% pure copper core offers superior heat dissipation, conductivity and ultra wide heat ranges
COLD-ROLLED THREADS: Prevents cross-threading and damage to cylinder heads
TRIVALENT METAL PLATING: Delivers superior anti-corrosion and anti-seizing properties, ensuring ease of installation and removal

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$6.79

With over 100 years of engineering expertise and more than 11 billion plugs sold, Autolite delivers exceptional quality. Designed and engineered in the USA, these spark plugs feature platinum-to-platinum firing, virtually eliminating gap erosion and reducing misfires. The OE design and full-platinum tips on both the center and side electrodes optimize engine performance for a longer life and improved fuel economy. The platinum ball welding process ensures a consistent point of contact for enhanced adhesion, while the tapered seat type further contributes to the plug’s superior durability.

Product Features:

Works to optimize engine performance for a longer life and improved fuel economy
OE design
Full-platinum tips; platinum on both the center and side electrodes to promote reduced gap wear
Platinum ball welding process provides a consistent point of contact for enhanced adhesion
Engineered in the USA: Developed with over 100 years of engineering expertise, ensuring high-quality and reliable performance.

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$3.49

Autolite has over 100 years of engineering experience and has sold over 11 billion plugs. Guaranteed to deliver quick starts, good fuel economy and smooth acceleration, Autoline Copper Core spark plugs are designed to meet or exceed OES design requirements. Consider upgrading to Autolite Platinum, Double Platinum or Iridium XP plugs for improved engine performance. Copper core plugs are the industry standard.

Product Features:

Copper-glass seal bonds insulator, terminal post center electrode together; assures full required voltage at spark gap; gas-tight seal (100% leak proof)
Multi-rib insulator reduces danger of “flash-over”
One-piece terminal post adds strength
Resistor reduces radio frequency interference (RFI) and electrode erosion
Quick Starts: Autolite Copper Core spark plugs are engineered to ensure your engine starts quickly and efficiently.
Good Fuel Economy: Designed to optimize fuel consumption, these spark plugs help you achieve better mileage.
Smooth Acceleration: Experience smoother and more responsive acceleration with Autolite Copper Core spark plugs.
OES Design Compliance: These spark plugs meet or exceed Original Equipment Service (OES) design requirements, ensuring reliable performance.
Tapered Seat Type: Featuring a tapered seat type, these spark plugs provide a secure fit and optimal performance.

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$3.79

U-Groove design provides better ignitability for increased engine efficiency.

Product Features:

Patented U-groove ground electrode design fires leaner mixtures than conventional plugs
Precision machine-rolled threads reduce seizing and cross-threading in delicate aluminum heads
Wide range of part numbers for thousands of applications, including classic and collector cars
Lasts twice as long as most conventional plugs
100% pre-fired to assure reliable operation
U-Groove Conventional

1984 Mercury Marquis Spark Plugs

More 1984 Mercury Marquis Spark Plugs

Essential 1984 Mercury Marquis Spark Plugs

Champion – Copper Plus Spark Plug: Dependable Performance, OE Replacement, RS12YC (Part No.401)

DENSO – PTF16TT Platinum TT Spark Plug (Part No.4509)

Accel – U-Groove Resistor Blister-Pak: Spark Plug (Part No.8179)

DENSO – Double Platinum Spark Plug: OE Performance, lasts 60K+ Miles, PT16EPR10 (Part No.5091)

NGK – Standard Spark Plug (Part No.F100037031NGK)

Dorman – Help – Spark Plug Non-Foulers – 18mm Tapered Seat (Part No.42002)

Champion – Copper Plus Spark Plug: Dependable Performance, OE Replacement, RV17YC (Part No.25)

Motorcraft – Original Equipment Copper Core Spark Plug (Part No.F1000194982MTR)

Autolite – Platinum Spark Plug: Fires Cleaner, Easier Starts, Quicker Acceleration (Part No.AP5145)

Autolite – Platinum Spark Plug: Fires Cleaner, Easier Starts, Quicker Acceleration (Part No.AP104)

Autolite Iridium – Iridium XP Finewire Spark Plug: Improved Durability, More Focused Ignition (Part No.XP5145)

Champion – Iridium Spark Plug: Maximum Performance, OE Replacement, RS14WYPB5 (Part No.9404)

Motorcraft – High-Performance Spark Plug: Enhances Fuel Efficiency (Part No.SP-450-X)

Bosch – OE Finewire Platinum Spark Plug (Part No.F1000420685BOS)

E3 – DiamondFIRE Automotive Spark Plug: More Power, Saves Gas (Part No.E3.44)

Autolite – Copper Spark Plug: Delivers Quick Starts, Good Fuel Economy, Smooth Acceleration (Part No.26)

ACDelco – Double Platinum Spark Plug: Original Equipment Replacement (Part No.41-948)

Motorcraft – Double Platinum Spark Plug: Enhances Durability & Reduces Misfires (Part No.SP-459)

Motorcraft – Spark Plug (Part No.SP-425-X)

Autolite Iridium – Iridium XP Finewire Spark Plug: Improved Durability, More Focused Ignition (Part No.XP106)

DENSO – PT16TT Platinum TT Spark Plug (Part No.4511)

Autolite – Copper Spark Plug: Delivers Quick Starts, Good Fuel Economy, Smooth Acceleration (Part No.5145)

Autolite – Double Platinum Spark Plug: Platinum Firing, Superior Durability, Longer Life (Part No.APP45)

Autolite – Platinum Spark Plug: Fires Cleaner, Easier Starts, Quicker Acceleration (Part No.AP26)

NGK – OE Series V-Power Nickel Spark Plug: V-Groove Tip Design, WR5 (Part No.2438)

Autolite – Double Platinum Spark Plug: Platinum Firing, Superior Durability, Longer Life (Part No.APP104)

Autolite – Copper Spark Plug: Delivers Quick Starts, Good Fuel Economy, Smooth Acceleration (Part No.2545)

DENSO – U-Groove Spark Plug: OE Performance, lasts 30K+ Miles, T16EPR-U (Part No.5022)

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