1978 Cadillac Eldorado Spark Plugs

Your 1978 Cadillac Eldorado 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 11 Spark Plugs to choose from for your 1978 Cadillac Eldorado, and our inventory prices range from as little as $3.49 up to $8.99.

On top of low prices, Advance Auto Parts offers 5 different trusted brands of Spark Plugs for the 1978 Cadillac Eldorado. We only sell parts from trusted brands like E3 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 86 reviews on our Spark Plugs for the 1978 Cadillac Eldorado 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 1978 Cadillac Eldorado

Champion – Double Platinum & Power Spark Plug Exceptional Perf OE Replacement RN14PMP5 (Part No.7031)

Double Platinum & Power Spark Plug Exceptional Perf OE Replacement RN14PMP5

from

$8.29
Champion® Double Platinum Power™ spark plugs deliver more powerful performance. Featuring exclusive Heat-Active™ alloy, platinum fine wire center electrode and platinum pad ground electrode provide maximum life and sharper spark focus.

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
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NGK – OE Series V-Power Nickel Spark Plug: V-Groove Tip Design, GR45 (Part No.4268)

OE Series V-Power Nickel Spark Plug: V-Groove Tip Design, GR45

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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
  • 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 GR45 model enhances ignitability and overall engine performance.
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Autolite – Double Platinum Spark Plug: Platinum Firing, Superior Durability, Longer Life (Part No.APP646)

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

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$6.49
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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Autolite – Copper Spark Plug: Delivers Quick Starts, Good Fuel Economy, Smooth Acceleration (Part No.646)

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

from

$3.49
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 cored center electrode for higher thermal conductivity
  • Specially engineered high nickel alloy center and ground electrode for extended life
  • High alumina ceramic for high dielectric strength
  • Leak proof, heat fused internal seal for durability
  • Multi-rib insulator prevents flash-over
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E3 – DiamondFIRE Automotive Spark Plug: More Power, Saves Gas (Part No.E3.46)

DiamondFIRE Automotive Spark Plug: More Power, Saves Gas

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$7.49
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. E3.46 is a 14mm, 0.750 reach plug with a gasket seat. It fits a wide variety of applications from the 60s to early 90s, especially import. E3.46 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.
  • Wide Compatibility: The E3.46 spark plugs are 14mm with a 0.750 reach and a gasket seat, making them suitable for a wide range of applications from the 1960s to early 1990s, especially for import vehicles.
  • Widely Available: The E3.46 spark plugs are widely stocked in automotive retail stores, ensuring easy availability for consumers.
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Autolite – Platinum Spark Plug: Fires Cleaner, Easier Starts, Quicker Acceleration (Part No.AP646)

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

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$4.49
Autolite Platinum spark plugs provide a center wire platinum firing tip for improved performance and durability. These plugs fire quicker and cleaner with less voltage, creating easier starts, quicker acceleration and improved fuel economy versus standard plugs.

Product Features:
  • Full platinum firing tip assures virtually no gap erosion and fewer misfires for a longer plug life
  • Manufactured with a center wire platinum firing tip for improved performance and durability
  • High nickel alloy side electrode resists electrical and chemical wear to maintain a precise gap for a longer lasting plug
  • Super conductive yttrium enhanced ground electrode provides superior heat transfer
  • Leak proof, heat fused resistor for added stability
  • Necked-down center electrode fires quicker and cleaner with less voltage for easier starts, quicker acceleration, and improved fuel economy
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ACDelco – RAPIDFIRE Premium Platinum Tip Copper Core Spark Plug: Reduces Misfires & Enhances Durability (Part No.4)

RAPIDFIRE Premium Platinum Tip Copper Core Spark Plug: Reduces Misfires & Enhances Durability

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$6.79
ACDelco Gold (Professional) RAPIDFIRE Spark Plugs are a high quality alternative to Original Equipment (OE) parts. These RAPIDFIRE Single Platinum Performance Spark Plugs are designed for everyday use and are a high quality replacement for many vehicles on the road today. These premium aftermarket spark plugs have high-quality suppressors that help prevent misfiring, an improved plug to boot seal, and a pure copper core for greater durability. These premium aftermarket replacement spark plugs are manufactured to meet your expectations for fit, form, and function. ACDelco Gold (Professional) parts are manufactured to meet your expectations for fit, form, and function, making them a smart choice for General Motors vehicles, as well as most makes and models, including special applications. These high-quality parts are backed by General Motors. Some ACDelco Gold parts may have formerly appeared as ACDelco Professional.

Product Features:
  • Solid state suppressor, with two-piece glass and brass seal, can help reduce radio frequency interference, regulates spark energy for long electrode life, and helps protect against high combustion pressures
  • Pure copper core provides great heat transfer and helps maximize plug durability
  • Platinum on center electrode enables superior spark characteristics and can reduce voltage requirements of the ignition system
  • Ribless insulator helps optimize plug to boot seal
  • Some ACDelco Gold parts may have formerly appeared as ACDelco Professional
  • Premium aftermarket replacement part
  • Manufactured to meet specifications for fit, form, and function for General Motors vehicles as well as most makes and models
  • High-Quality Suppressors: These spark plugs are equipped with high-quality suppressors that help prevent misfiring, ensuring smooth and efficient engine operation.
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ACDelco – Copper Core Spark Plug: Original Equipment Replacement (Part No.R45XLS6)

Copper Core Spark Plug: Original Equipment Replacement

from

$4.99
ACDelco Professional Conventional Spark Plugs are designed for reliability and efficient performance, and are a high quality replacement for many vehicles on the road today. Their high-quality copper cores and outstanding suppression characteristics deliver reliable performance. They are also available for Marine applications. These premium aftermarket replacement spark plugs are manufactured to meet your expectations for fit, form, and function.

Product Features:
  • Black Onyx coating helps reduce corrosion
  • Copper core provides great heat transfer and helps maximize plug durability
  • Ribbed suppressor seal extends resistance and helps prevent spark ‘flash over’ and misfires
  • Nickel-chrome alloy sheathing helps prevent corrosion on center electrode
  • Available for use in Marine applications
  • 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
  • High-Quality Copper Core: ACDelco Professional Conventional Spark Plugs feature high-quality copper cores, ensuring reliable performance and efficient operation.
  • Nickel Center Electrode Tip: Designed with a nickel center electrode tip, these spark plugs provide durability and consistent performance.
  • Outstanding Suppression Characteristics: These spark plugs offer excellent suppression characteristics, contributing to their reliable performance in various driving conditions.
  • Premium Aftermarket Replacement: Manufactured to meet expectations for fit, form, and function, these spark plugs serve as a high-quality replacement for original equipment.
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NGK – G-Power Spark Plug: Single Platinum Tip Design, GR45GP (Part No.3142)

G-Power Spark Plug: Single Platinum Tip Design, GR45GP

from

$5.29
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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Autolite Iridium – Iridium XP Finewire Spark Plug: Improved Durability, More Focused Ignition (Part No.XP646)

Iridium XP Finewire Spark Plug: Improved Durability, More Focused Ignition

from

$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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Champion – Platinum Power Spark Plug: Powerful Perfromance, OE Replacement, RN14PMC5 (Part No.3031)

Platinum Power Spark Plug: Powerful Perfromance, OE Replacement, RN14PMC5

from

$4.49
Champion Platinum Power spark plugs deliver powerful performance. Made from exclusive Heat-Active alloy, a fine-wire center electrode and V-trimmed ground electrode provides sharp spark focus.

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
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FAQs for 1978 Cadillac Eldorado Spark Plugs

What are the most popular Spark Plugs for the 1978 Cadillac Eldorado?

With 5 brands you can trust, our most popular Spark Plugs for the 1978 Cadillac Eldorado parts are:

What are the best aftermarket Spark Plugs for the 1978 Cadillac Eldorado?

See what past customers had to say about our highest-rated Spark Plugs for the 1978 Cadillac Eldorado:
Copper Spark Plug: Delivers Quick Starts, Good Fuel Economy, Smooth Acceleration
from $3.49
(5)
Copper Spark Plug: Delivers Quick Starts, Good Fuel Economy, Smooth Acceleration
“Though copper plugs don’t last as long as platinum, they run smoother in older cars that lack the sophisticated ignition timing computers of the newer”