Name: Copper Spark Plug: Delivers Quick Starts, Good Fuel Economy, Smooth Acceleration
Brand: Autolite
SKU: 3923
Price: 3.49 USD
Rating: 4.5 (53 reviews)

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$3.49

Autolite® Copper spark plugs deliver quick starts, good fuel economy and smooth acceleration.

Product Features:

One-Piece terminal stud provides a reliable high voltage electrical connection
High alumina multi-rib insulator helps prevent flash-over which can lead to misfires
Heat-fused glass composite resistor center seal provides high performance EMI noise suppression and a 100 percent leak-proof seal
Solid copper core center electrode provides optimal thermal and electrical conductivity for better performance in all driving conditions
High nickel alloy side electrode resists electrical and chemical wear providing excellent durability
2 year limited warranty

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$6.79

Motorcraft Spark Plugs are original equipment on Ford Motor Company vehicles, engineered to meet strict Ford engineering standards for unmatched performance and reliability. These spark plugs are precisely matched to specific engines, enhancing durability, eliminating misfires, reducing fuel consumption, and optimizing emissions. They are resistant to oxidation and arc erosion, feature a multi-rib insulator to protect against misfires, and offer service intervals of up to 100,000 miles. Backed by Motorcraft’s Service Parts Warranty, these spark plugs are an exact fit for Ford, Lincoln, and Mercury vehicles and are designed with high-quality materials to provide reliable performance for almost any application. Motorcraft ignition components also help prevent false check engine lights, ensuring your vehicle runs smoothly and efficiently.

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.
Engineered for Ford Vehicles: Motorcraft Spark Plugs are original equipment on Ford, Lincoln, and Mercury vehicles, ensuring a perfect fit and optimal performance.

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$3.49

OE Performance, lasts 30K+ Miles, K16GPR-U11. The unique U-Groove ground electrode is one of the finest features of DENSO spark plugs, designed to fire leaner mixtures than conventional plugs for improved ignitability. Precision machine-rolled threads reduce seizing and cross-threading in delicate aluminum heads, ensuring a secure fit. With a wide range of part numbers for thousands of applications, including classic and collector cars, these spark plugs last twice as long as most conventional plugs. Each plug is 100% pre-fired to assure reliable operation, featuring a nickel center electrode tip and a flat seat type for optimal performance.

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
Long-Lasting Durability: Lasts over 30,000 miles, twice as long as most conventional spark plugs, providing extended performance and reliability.

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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. E3.56 is a 14mm, 0.750 reach plug with a gasket seat. It fits a wide variety of late model applications, especially import. 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.

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$10.56

The DENSO Double-Platinum plug features platinum on both the center and ground electrodes. The precious metal fights corrosion and erosion, ensuring superior spark performance and maximum spark plug life. DENSO Double Platinum spark plugs incorporate the precious metal on both the center and ground electrodes, not just on the center electrode as with conventional platinum plugs. The result is a significant improvement in spark plug life.

Product Features:

Platinum center electrode
Platinum ground electrode
Premium shell construction with machine-rolled threads
Sustained spark performance over 60,000 miles
Reduced secondary required voltage, increased ignition efficiency DENSO engineering studies show that Double Platinum plugs can run longer with reduced erosion, minimizing spark gap growth throughout the life of the plug.

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$3.89

Denso Spark Plug Denso’s standard plugs have always offered a patented U-groove ground electrode producing for a larger, hotter spark. Copper core for better thermal conductivity. Machine rolled threads to reduce cross-threading and seizing . The plug insulator is constructed of purified alumina powder for extreme stress with 5 ribs to prevent flashover.

Product Features:

U-Groove Ground Electrode Promotes Ignitability and Decreases Quenching
Fully Projected Insulator Reduces Carbon Fouling
Machine Rolled Threads Prevent Seizing or Cross Threading During Installation and Removal
100% Pre-Fired to Assure the Highest Quality Possible
Purified Alumina Powder Insulator Provides Exceptional Strength and Thermal Conductivity
Five Rib Insulator Prevents Flashover
Copper-Glass Seal Bonds Center Electrode and Insulator for a Gas-Tight Seal

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$9.49

Champion® Double Platinum Power spark plugs deliver more powerful performance with their premium design. Featuring a platinum center and ground electrode, these spark plugs offer greater wear resistance and maintain a stable operating temperature under all engine loads. The fine-wire center electrode ensures greater ignitability, while the V-trimmed ground electrode promotes sharper spark focus. The exclusive Heat-Active alloy allows the electrodes to reach optimal temperature, ensuring maximum life and performance. With a platinum firing tip, flat seat type, and built-in resistor, these spark plugs are designed for exceptional performance and durability.

Product Features:

Double Platinum Power – Premium Spark Plug. More Powerful Performance.
Platinum center and ground electrode for greater wear resistance
Maintains stable operating temperature under all engine loads
Fine-wire center electrode for greater ignitability
V-trimmed ground electrode promotes sharper spark focus
Heat-Active alloy allows electrodes to reach optimal temperature
Built-in Resistor and Flat Seat Type: Designed with a built-in resistor and flat seat type for exceptional performance and durability.

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$5.99

NGK G-Power Platinum spark plugs are the best single platinum spark plugs at an economical price. G-Power plugs feature a fine wire platinum center electrode and a trapezoidal cut ground electrode that offers increased durability, improved fuel efficiency, lower emissions, faster starts and quicker acceleration over conventional nickel spark plugs. An excellent upgrade for vehicles which used nickel alloy spark plugs originally. For better performance consider upgrading to a NGK Iridium IX plug. For even greater performance consider upgrading to a NGK RUTHENIUM HX plug.

Product Features:

SINGLE PLATINUM TIP: Fine wire 0.6 millimeter platinum tip center electrode ensures improved durability and a consistently stable spark
PLATINUM ALLOY: G-Power platinum provides exceptional value with increased performance and longer service intervals than factory nickel plugs
TRAPEZOIDAL CUT GROUND ELECTRODE: Reduces quenching design produces improved ignitability and 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
RECOMMENDED USAGE: Lower cost alternative to double precious metal spark plugs or as an upgrade to OE nickel alloy spark plugs

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$10.99

Optimal Performance, Durability, Ignitability. The Autolite Iridium Ultra is an engineered OE replacement iridium spark plug featuring a laser-welded 0.5mm proprietary iridium alloy finewire center electrode that ensures optimal fuel efficiency, acceleration, and focused ignitability. Its nickel-plated shell resists corrosion, while the high-alumina ceramic insulator provides increased strength. Additionally, the proprietary platinum sidewire technology enhances durability and performance, making it a top choice for reliable ignition. It also features a resistor type and a flat seat type for added compatibility and performance.

Product Features:

Autolite Iridium Ultra is an engineered OE replacement iridium spark plug.
A laser-welded 0.5mm proprietary iridium alloy finewire center electrode provides optimal fuel efficiency, acceleration and focused ignitability.
Nickel-plated shell to resist corrosion.
High-alumina ceramic insulator for increased strength.
Laser welded 0.5mm Iridium finewire center electrode.
Proprietary platinum sidewire technology.

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$3.84

Denso Spark Plug Denso’s standard plugs have always offered a patented U-groove ground electrode producing for a larger, hotter spark. Copper core for better thermal conductivity. Machine rolled threads to reduce cross-threading and seizing . The plug insulator is constructed of purified alumina powder for extreme stress with 5 ribs to prevent flashover.

Product Features:

U-Groove Ground Electrode Promotes Ignitability and Decreases Quenching
Fully Projected Insulator Reduces Carbon Fouling
Machine Rolled Threads Prevent Seizing or Cross Threading During Installation and Removal
100% Pre-Fired to Assure the Highest Quality Possible
Purified Alumina Powder Insulator Provides Exceptional Strength and Thermal Conductivity
Five Rib Insulator Prevents Flashover
Copper-Glass Seal Bonds Center Electrode and Insulator for a Gas-Tight Seal

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$15.79

Original equipment manufacturer approved NGK Laser Platinum spark plugs provide high ignitibility and longer service life compared to conventional spark plugs. Recommended for modern vehicles using distributorless ignition systems (DIS) for enhanced plug service life, these spark plugs feature dual-platinum surfaces that ensure a slower wear rate while providing a more stable idle, superior anti-fouling, improved fuel efficiency, and lower emissions. The platinum center electrode tip and gasket seat type further contribute to their exceptional performance and durability.

Product Features:

Recommended for modern vehicles using distributorless ignition systems (DIS) for enhanced plug service life
Enhanced Ignitibility: The NGK Laser Platinum Spark Plug is designed to provide superior ignitibility, ensuring reliable engine starts and smooth performance.
Longer Service Life: Featuring dual-platinum surfaces, these spark plugs offer a slower wear rate, resulting in a significantly longer service life compared to conventional spark plugs.
Improved Fuel Efficiency: The advanced design of the NGK Laser Platinum Spark Plug helps improve fuel efficiency, making it an ideal choice for modern vehicles.
Superior Anti-Fouling: With its platinum center electrode tip, this spark plug provides excellent anti-fouling properties, ensuring consistent performance over time.
Lower Emissions: The NGK Laser Platinum Spark Plug contributes to lower emissions, supporting a cleaner and more environmentally friendly driving experience.

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$3.99

This spark plug features a platinum twin-tip design and a titanium-enhanced ground strap, ensuring superior performance and longevity. The center electrode tip material is made of platinum, providing excellent durability and consistent spark. Additionally, the flat seat type ensures a secure fit, making it an ideal choice for reliable and efficient ignition in your vehicle.

Product Features:

Platinum Twin-Tip Design: The Denso Platinum TT Spark Plug features a unique twin-tip design, enhancing ignition efficiency and performance.
Titanium-Enhanced Ground Strap: Equipped with a titanium-enhanced ground strap, this spark plug ensures superior durability and longevity.
Platinum Center Electrode Tip: The center electrode tip is made of platinum, providing excellent durability and a consistent spark for reliable ignition.
Superior Performance: Designed for enhanced ignition, this spark plug offers reliable and efficient performance, making it a top choice for vehicle maintenance.

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$4.79

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
Enhanced Ignitability: The V-cut nickel alloy center electrode and concave ground electrode design of NGK V-Power spark plugs provide quicker starts and smoother idle.
OE Application Specific: Engineered specifically for Original Equipment (OE) applications, ensuring compatibility and reliable performance.
V-Groove Tip Design: The unique V-Groove tip design of the BKR6EY model enhances ignitability and overall engine performance.

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$11.99

NGK Iridium IX spark plugs are specifically designed for the performance enthusiast. Iridium IX provides outstanding acceleration, high fuel efficiency and durability. NGK Iridium IX plugs offer extreme ignitability and exceptional anti-fouling. Tapered cut ground electrode provides improved starting, idling and throttle response. The Iridium fine wire center electrode’s durability is six times harder than platinum. Iridium alloy’s extremely high melting point is perfect for today’s engines. For even greater performance consider upgrading to an NGK Ruthenium HX plug.

Product Features:

SINGLE IRIDIUM TIP: Fine wire 0.6 millimeter iridium tip center electrode ensures high durability and a consistently stable spark
IRIDIUM ALLOY CENTER ELECTRODE: Iridium’s density (6x that of platinum) and extremely high melting point is perfect for modern high efficiency engines
TAPERED CUT GROUND ELECTRODE: Reduced quenching design produces outstanding ignitability, improved acceleration, fuel efficiency and durability
SOLID COPPER CORE: 98% pure copper core offers superior heat dissipation, conductivity and ultra wide heat ranges
TRIVALENT METAL PLATING: Delivers superior anti-corrosion and anti-seizing properties, ensuring ease of installation and removal
RECOMMENDED USAGE: Modified or high performance applications, or as an upgrade to OE nickel alloy spark plugs

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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

1994 Nissan D21 Spark Plugs

More 1994 Nissan D21 Spark Plugs

Essential 1994 Nissan D21 Spark Plugs

Autolite – Copper Spark Plug: Delivers Quick Starts, Good Fuel Economy, Smooth Acceleration (Part No.3923)

Motorcraft – High-Durability Spark Plug: Reduces Misfires & Optimizes Emissions (Part No.SP-445-AX)

DENSO – U-Groove Spark Plug: OE Performance, lasts 30K+ Miles, K16GPR-U11 (Part No.3135)

E3 – DiamondFIRE Automotive Spark Plug: More Power, Saves Gas (Part No.E3.56)

DENSO – Double Platinum Spark Plug (Part No.F100032276ND)

DENSO – Standard U-Groove Spark Plug (Part No.F100052021ND)

Champion – Double Platinum & Power Spark Plug Exceptional Perf OE Replacement RC12PMPB4 (Part No.7318)

NGK – G-Power Spark Plug: Single Platinum Tip Design, ZFR5EGP (Part No.7096)

Autolite Iridium – Iridium Ultra Finewire Spark Plug: Optimal Performance, Durability, Ignitability (Part No.AI3923)

DENSO – Standard U-Groove Spark Plug (Part No.F100052025ND)

NGK – Laser Platinum Spark Plug – Enhanced Ignitibility & Longer Service Life (Part No.4793)

DENSO – Platinum TT Spark Plug with Twin-Tip Design for Enhanced Ignition (Part No.4503)

NGK – OE Series V-Power Nickel Spark Plug: V-Groove Tip Design, BKR6EY (Part No.3696)

NGK – Iridium IX Spark Plug: Single Iridium Fine Wire, BKR6EIX (Part No.6418)

Dorman – Help – Spark Plug Non-Foulers – 14mm Gasket Seat Long Reach (Part No.42004)

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