1991 Toyota 4Runner Spark Plugs

Your 1991 Toyota 4Runner might be the best vehicle you’ve ever owned. Or you may just be struggling to keep it highway-approved. No matter the situation, Advance Auto Parts has the Spark Plugs you desperately need.

We currently carry 47 Spark Plugs to choose from for your 1991 Toyota 4Runner, and our inventory prices range from as little as $2.49 up to $16.99.

On top of low prices, Advance Auto Parts offers 7 different trusted brands of Spark Plugs for the 1991 Toyota 4Runner. We only sell parts from trusted brands like Autolite so that you can find quality parts you can count on.

Don’t take our word for it – check out customer ratings and reviews to buy with confidence. We have 1,276 reviews on our Spark Plugs for the 1991 Toyota 4Runner from previous customers.

Have parts delivered straight to your home, or find the nearest Advance Auto Parts store to check out our Spark Plugs stock in-person!

Spark Plugs for Your 1991 Toyota 4Runner

Autolite – Platinum Spark Plug: Fires Cleaner, Easier Starts, Quicker Acceleration (Part No.AP3924)

Platinum Spark Plug: Fires Cleaner, Easier Starts, Quicker Acceleration

from

$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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DENSO – Iridium TT Spark Plug: Ultimate Endurance and Power, 0.4mm Iridium Tip, last 100K+ Miles, IK16TT (Part No.4701)

Iridium TT Spark Plug: Ultimate Endurance and Power, 0.4mm Iridium Tip, last 100K+ Miles, IK16TT

from

$10.99
Durability of an OE style plug combined with Power & Torque of high performance.

Product Features:
  • 0.4mm Iridium Center Electrode: World’s Smallest Diameter that maximizes firing potential
  • 0.7mm Needle Tip Ground Electrode: Promotes higher spark energy and less heat quenching
  • DENSO Patented Optimized Iridium-Rhodium Alloy Formula: Highest concentration of Iridium vs. competitors for greater durability
  • DENSO Patented 360 degree laser welding process: Ensuring exceptional quality bond and structural strength with the Iridium Center Electrode
  • Durability of an OE style plug combined with Power & Torque of high performance.
  • Withstands temperatures greater than 4000┬░ Fahrenheit
  • Iridium TT
  • Ultimate Endurance and Power: The DENSO Iridium TT Spark Plug features a 0.7mm Iridium Tip, ensuring over 100,000 miles of uncompromised performance.
  • Advanced Twin-Tip Technology: Developed from Original Equipment Specification Super Ignition Plug (SIP) design, combining a Fine Wire Iridium Center Electrode with a Needle Tip Platinum Ground Electrode.
  • Enhanced Fuel Economy and Lower Emissions: Drive around the Earth over 4 times with improved fuel efficiency and reduced emissions.
  • Premium Materials: Features an Iridium Center Electrode Tip and a Flat Seat Type for optimal performance and durability.
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Autolite – Double Platinum Spark Plug: Platinum Firing, Superior Durability, Longer Life (Part No.APP3924)

Double Platinum Spark Plug: Platinum Firing, Superior Durability, Longer Life

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$6.79
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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NGK – G-Power Spark Plug: Single Platinum Tip Design, BKR5EGP (Part No.7090)

G-Power Spark Plug: Single Platinum Tip Design, BKR5EGP

from

$6.29
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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NGK – OE Series Standard Nickel Spark Plug: Conventional Tip Design, BPR5ES (Part No.7734)

OE Series Standard Nickel Spark Plug: Conventional Tip Design, BPR5ES

from

$4.99
NGK Standard spark plugs (in the iconic NGK ‘yellow box’ packaging) are a proven OE cornerstone and technology customers have relied on for decades. Engineered specifically for OE applications, NGK Standard spark plugs provide OE quality nickel alloy reli

Product Features:
  • ACTUAL OE or EQUIVALENT DESIGN: OEM quality construction nickel alloy center electrode 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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Champion – Copper Plus Spark Plug: Dependable Performance, OE Replacement, RN12YC (Part No.404)

Copper Plus Spark Plug: Dependable Performance, OE Replacement, RN12YC

from

$4.49
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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DENSO – Iridium Power Spark Plug: Maximum Spark Energy, 0.4mm Iridium Tip, IK16 (Part No.5303)

Iridium Power Spark Plug: Maximum Spark Energy, 0.4mm Iridium Tip, IK16

from

$11.79
Increased performance with World’s smallest Iridium Center Eletrode (0.4mm).

Product Features:
  • World’s smallest Iridium Center Electrode (0.4mm) for improved spark for maximum combustion
  • Patented 360-degree laser welding assembly process
  • U-groove and taper cut ground electrode to maximize flame propagation.
  • Withstands temperatures greater than 4000┬░ Fahrenheit
  • Burnished nickel plating for high temperature endurance and superior corrosion resistance
  • Wide range of part numbers for thousands of applications, including classic and collector cars
  • Iridium Power
  • Superior Performance: Engineered for maximum performance under extreme conditions, this spark plug delivers more horsepower, faster and easier starts, and fewer misfires under heavy loads.
  • Enhanced Fuel Efficiency: Thanks to its advanced design and patented technology, the Iridium Power plug improves fuel efficiency, making it an economical choice for your vehicle.
  • Low Voltage Requirement: The DENSO Iridium Power spark plug requires 5,000 volts less to fire compared to conventional spark plugs, ensuring reliable ignition with lower energy consumption.
  • Durable Iridium Material: Constructed with a durable iridium center electrode tip and a flat seat type, this spark plug offers long-lasting performance and reliability.
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NGK – OE Series V-Power Nickel Spark Plug: V-Groove Tip Design, BKR5EYA (Part No.2087)

OE Series V-Power Nickel Spark Plug: V-Groove Tip Design, BKR5EYA

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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 OE applications, ensuring compatibility and reliable performance.
  • V-Groove Tip Design: The unique V-groove tip design enhances ignitability and overall engine performance.
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NGK – G-Power Spark Plug: Single Platinum Tip Design, BPR5EGP (Part No.7082)

G-Power Spark Plug: Single Platinum Tip Design, BPR5EGP

from

$5.79
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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DENSO – U-Groove Spark Plug: OE Performance, lasts 30K+ Miles, W16EXR-U (Part No.3031)

U-Groove Spark Plug:  OE Performance, lasts 30K+ Miles, W16EXR-U

from

$2.79
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
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Champion – Platinum Power Spark Plug: Powerful Perfromance, OE Replacement, RC12PYC (Part No.3071)

Platinum Power Spark Plug: Powerful Perfromance, OE Replacement, RC12PYC

from

$4.79
Champion® Platinum Power spark plugs deliver powerful performance with their premium design. Featuring a platinum center electrode for long life and a fine-wire center electrode for greater ignitability, these spark plugs ensure optimal engine performance. The V-trimmed ground electrode promotes sharper spark focus, while the exclusive Heat-Active alloy allows the electrodes to reach optimal temperature. Additionally, the platinum-tipped center wire resists wear and helps maintain the proper gap specification throughout the life of the plug, making it a reliable choice for your vehicle.

Product Features:
  • Platinum Power- Premium Spark Plug. Powerful Performance.
  • Platinum center electrode for long life
  • Fine-wire center electrode for greater ignitability
  • V-trimmed ground electrode promotes sharper spark focus
  • Heat-Active alloy allows electrodes to reach optimal temperature
  • Platinum tipped center wire resists wear and helps to maintain proper gap spec over life of the plug
  • Platinum Center Electrode: The Champion Platinum Power Spark Plug features a platinum center electrode for extended durability and long-lasting performance.
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Autolite – Platinum Spark Plug: Fires Cleaner, Easier Starts, Quicker Acceleration (Part No.AP64)

Platinum Spark Plug: Fires Cleaner, Easier Starts, Quicker Acceleration

from

$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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DENSO – U-Groove Spark Plug: OE Performance, lasts 30K+ Miles, K16R-U (Part No.3119)

U-Groove Spark Plug:  OE Performance, lasts 30K+ Miles, K16R-U

from

$4.29
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
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NGK – Iridium IX Spark Plug: Single Iridium Fine Wire, BKR5EIX (Part No.6341)

Iridium IX Spark Plug: Single Iridium Fine Wire, BKR5EIX

from

$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
  • Outstanding Performance: NGK Iridium IX spark plugs are specifically designed for performance enthusiasts, providing exceptional acceleration and high fuel efficiency.
  • Extreme Durability: The Iridium fine wire center electrode is six times harder than platinum, ensuring long-lasting durability and reliability.
  • Enhanced Ignitability: These spark plugs offer extreme ignitability and exceptional anti-fouling, making them ideal for high-performance engines.
  • Improved Engine Response: The tapered cut ground electrode enhances starting, idling, and throttle response for a smoother driving experience.
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Champion – Platinum Power Spark Plug: Powerful Perfromance, OE Replacement, RN14PMC (Part No.3405)

Platinum Power Spark Plug: Powerful Perfromance, OE Replacement, RN14PMC

from

$3.99
Champion® Platinum Power spark plugs deliver powerful performance with their premium design. Featuring a platinum center electrode for long life and a fine-wire center electrode for greater ignitability, these spark plugs ensure optimal engine performance. The V-trimmed ground electrode promotes sharper spark focus, while the exclusive Heat-Active alloy allows the electrodes to reach optimal temperature. Additionally, the platinum-tipped center wire resists wear and helps maintain the proper gap specification throughout the life of the plug. With a flat seat type and integrated resistor, this spark plug is an ideal OE replacement.

Product Features:
  • Platinum Power- Premium Spark Plug. Powerful Performance.
  • Platinum center electrode for long life
  • Fine-wire center electrode for greater ignitability
  • V-trimmed ground electrode promotes sharper spark focus
  • Heat-Active alloy allows electrodes to reach optimal temperature
  • Platinum tipped center wire resists wear and helps to maintain proper gap spec over life of the plug
  • Integrated Resistor and Flat Seat Type: Equipped with an integrated resistor and flat seat type, making it an ideal OE replacement for various engines.
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Motorcraft – Spark Plug (AGSP32FP) (Part No.SP-485)

Spark Plug (AGSP32FP)

from

$4.79
Motorcraft Spark Plugs are original equipment on Ford Motor Company vehicles engineered to meet strict Ford engineering standards to provide original equipment performance and reliability. Delivering performance, reliability and confidence, Motorcraft spa

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.
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DENSO – Iridium Power Spark Plug: Maximum Spark Energy, 0.4mm Iridium Tip, IW16 (Part No.5305)

Iridium Power Spark Plug: Maximum Spark Energy, 0.4mm Iridium Tip, IW16

from

$11.99
Increased performance with World’s smallest Iridium Center Eletrode (0.4mm).

Product Features:
  • World’s smallest Iridium Center Electrode (0.4mm) for improved spark for maximum combustion
  • Patented 360-degree laser welding assembly process
  • U-groove and taper cut ground electrode to maximize flame propagation.
  • Withstands temperatures greater than 4000┬░ Fahrenheit
  • Burnished nickel plating for high temperature endurance and superior corrosion resistance
  • Wide range of part numbers for thousands of applications, including classic and collector cars
  • Iridium Power
  • Superior Performance: Patented technology allows the Iridium Power plug to outperform any other spark plug on the market, delivering more horsepower and better fuel efficiency.
  • Low Voltage Requirement: Requires 5,000 volts less to fire compared to conventional spark plugs, making it highly efficient and reliable under extreme conditions.
  • Enhanced Engine Starts: Experience faster and easier engine starts with fewer misfires, even under heavy loads, thanks to the advanced design of the DENSO Iridium Power spark plug.
  • Durable Iridium Material: Constructed with a durable iridium center electrode tip and a flat seat type, ensuring long-lasting performance and reliability.
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Champion – Double Platinum & Power Spark Plug Exceptional Perf OE Replacement RC12PYP (Part No.7071)

Double Platinum & Power Spark Plug Exceptional Perf OE Replacement RC12PYP

from

$6.99
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.

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
  • OE Replacement: Designed as an OE replacement, ensuring compatibility and reliable performance for your vehicle.
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DENSO – Iridium Long-Life Spark Plug: OE Performance, last 100K+ Miles, SK16PR-F8 (Part No.3435)

Iridium Long-Life Spark Plug:  OE Performance, last 100K+ Miles, SK16PR-F8

from

$16.99
Manufactured to the strictest OE performance, durability and emissions standards.

Product Features:
  • Latest OE technology with DENSO’s patented Iridium Alloy (90% Ir) and fine wire center electrode
  • Platinum ground electrode for extended life
  • DENSO Patented 360 degree laser welding process: Ensuring exceptional quality bond and structural strength with the Iridium Center Electrode
  • Sustained spark performance over 100,000 miles
  • Lasts up to three times as long as conventional plugs
  • Endures extreme temperatures greater than 4,000 degrees F associated with high-performance ignition and special fuel systems
  • Iridium Long Life
  • Enhanced Engine Performance: Enjoy more horsepower, faster and easier starts, and fewer misfires under heavy loads, thanks to the advanced properties of DENSO’s Iridium alloy.
  • Fuel Efficiency: The DENSO Iridium Long Life plug helps in better conservation of fuel, making it an eco-friendly choice for your vehicle.
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Motorcraft – Spark Plug (Part No.SP-406)

Spark Plug

from

$2.49
The only parts recommended by Ford Motor Company for Ford, Lincoln, and Mercury vehicles.Long Service Intervals: 100,000 mile service interval, High-Strength Steel High Thread, Platinum-Iridium, Fine-Wire Double Platinum, 60,000-100,000 mile service interval, Up to 60,000 mile service interval: Nickel, Standard Copper Core.
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E3 – DiamondFIRE Automotive Spark Plug: More Power, Saves Gas (Part No.E3.48)

DiamondFIRE Automotive Spark Plug: More Power, Saves Gas

from

$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. E3.48 is a 14mm, 0.750 reach plug with a gasket seat. It fits a wide variety of late model applications, especially import. E3.48 is widely stocked in automotive retail stores. 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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Champion – Champion Copper Plus- Single Card – RC12YC (Part No.71-1)

Champion Copper Plus- Single Card - RC12YC

from

$4.99
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.
  • Copper core center electrode allows for accurate control of heat range for longer life
  • Patented TinTac and ULTRASEAL coated shell for maximum corrosion resistance
  • Patented SAC-9 semiconductor resistor for maximum EMI & RFI suppression
  • Built to ISO and SAE standards for proven performance
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Champion – Copper Plus Spark Plug RC12YC: Dependable Performance & Durability (Part No.71)

Copper Plus Spark Plug RC12YC: Dependable Performance & Durability

from

$4.99
This Champion spark plug features a copper core electrode that provides increased conductivity and heat control for reliable performance. 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 copper alloy center electrode tip and flat seat type further enhance its reliability, making it a top choice for consistent engine performance.

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
  • Reliable Engine Performance: Featuring a nickel copper alloy center electrode tip and flat seat type, this spark plug ensures consistent and reliable engine performance.
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Autolite – Copper Spark Plug: Delivers Quick Starts, Good Fuel Economy, Smooth Acceleration (Part No.3924)

Copper Spark Plug: Delivers Quick Starts, Good Fuel Economy, Smooth Acceleration

from

$3.79
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:
  • 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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Autolite – Racing Resistor Spark Plug: Enables Performance, Handles Intense Conditions (Part No.AR3924)

Racing Resistor Spark Plug: Enables Performance, Handles Intense Conditions

from

$5.29
The ground electrode is cut-back from the center electrode to provide a gap. The face of the ground electrode is concave to provide a constant gap to the center electrode. This plug is designed use in all aftermarket cylinder heads used in different types of racing venues including oval and road racing.

Product Features:
  • Opens spark face for better ignitability of flame kernel
  • Retains less heat, transfers heat to shell faster – reduces risk of pre-ignition
  • Dyno testing has shown proven power gains
  • Cut-back ground electrode evolved from practice of grinding back the side electrode
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NGK – OE Series Standard Nickel Spark Plug: Conventional Tip Design, BKR5ES (Part No.2460)

OE Series Standard Nickel Spark Plug: Conventional Tip Design, BKR5ES

from

$4.99
NGK Standard spark plugs (in the iconic NGK ‘yellow box’ packaging) are a proven OE cornerstone and technology customers have relied on for decades. Engineered specifically for OE applications, NGK Standard spark plugs provide OE quality nickel alloy reliable performance and design. NGK’s legendary high grade alumina silicate ceramic creates a stronger insulator for optimal dielectric performance, while triple gasket sealing prevents combustion gas leakage. Solid 98% pure copper core offers superior heat dissipation, conductivity and ultra wide heat ranges. 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 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
  • Triple Gasket Sealing: Prevents combustion gas leakage, ensuring efficient engine performance.
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NGK – OE Series V-Power Nickel Spark Plug: V-Groove Tip Design, BPR5EY (Part No.1233)

OE Series V-Power Nickel Spark Plug: V-Groove Tip Design, BPR5EY

from

$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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ACDelco – Double Platinum Spark Plug (Part No.41-800)

Double Platinum Spark Plug

from

$9.79
ACDelco Professional Double Platinum Spark Plugs are premium aftermarket plugs, and are a high quality replacement for many vehicles on the road today. With a copper core and double platinum pads on the center electrode, these plugs are designed to deliver long-lasting performance. These premium aftermarket replacement spark plugs are manufactured to meet your expectations for fit, form, and function.

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
  • Pure copper core results in cooler electrode temperature for maximized durability and fouling resistance
  • 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
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FAQs for 1991 Toyota 4Runner Spark Plugs

What are the most popular Spark Plugs for the 1991 Toyota 4Runner?

With 7 brands you can trust, our most popular Spark Plugs for the 1991 Toyota 4Runner parts are:
Iridium XP Finewire Spark Plug: Improved Durability, More Focused Ignition
from $9.99
This product is not rated
Iridium XP Finewire Spark Plug: Improved Durability, More Focused Ignition
Spark Plugs

What are the best aftermarket Spark Plugs for the 1991 Toyota 4Runner?

See what past customers had to say about our highest-rated Spark Plugs for the 1991 Toyota 4Runner:
Champion Copper Plus- Single Card - RC12YC
from $4.99
(140)
Champion Copper Plus- Single Card – RC12YC
“they work just fine”
Platinum TT Spark Plug with Twin-Tip Design for Enhanced Ignition
from $3.99
(105)
Platinum TT Spark Plug with Twin-Tip Design for Enhanced Ignition
“Perfect fit! Excellent product.”