Name: Iridium XP Finewire Spark Plug: Improved Durability, More Focused Ignition
Brand: Autolite Iridium
SKU: XP3924
Price: 9.99 USD

from

$9.99

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

from

$9.49

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

from

$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.
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

from

$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

from

$13.05

3X longer service life compared to standard copper plugs Bosch Double Platinum spark plugs are engineered to extend performance life and durability. The fine wire design of the center electrode improves ignitability and performance in your engine while the platinum tip on both the center and ground electrodes ensure longer life. All backed by a 6-year performance satisfaction guarantee. Center Electrode Core Material: Nickel-Yttrium and Copper and Platinum – Center Electrode Tip Material: Platinum – Ground Electrode Tip Material: Nickel-Yttrium and Platinum

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

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

from

$9.99

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

from

$9.29

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 spark plugs are available for a broad range of applications, including domestic and import cars and trucks of all makes and sizes.

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.

from

$15.99

NGK Ruthenium HX High Ignitability spark plugs are the best in class plug for todays modern vehicles. Patented Ruthenium technology offers the most advance tip technology and delivers the highest performance and life expectancy. Created from advanced OE t

Product Features:

HIGH IGNITABILITY DOUBLE FINE ELECTRODE DESIGN: Combines 0.6 millimeter ruthenium center with opposed fine wire platinum ground electrode
RUTHENIUM ALLOY CENTER ELECTRODE: NGK’s patented ruthenium technology produces maximum performance, ignitability & durability at high temperatures
PLATINUM PIN TYPE GROUND ELECTRODE: Provides more complete fuel burn, quicker throttle response, smoother idle and better cold starts
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: Modern vehicles using OE DFE type spark plugs or for those seeking an aftermarket plug with the latest OE technology

from

$7.49

SPARK PLUG

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)

from

$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 sea
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

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

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

from

$12.99

NGK Laser Platinum spark plugs provide high ignitability and longer service life compared to conventional nickel spark plugs. Laser Platinum plugs are tested to the highest standards to ensure quality and durability. Engineered specifically for OE applications. Laser platinum plugs provide stable idling, superior anti-fouling, improved fuel efficiency and lower emissions. High-grade pure alumina ceramic and 98% pure copper core prevents spark plug from overheating and provides reliable starts. Most Laser Platinum spark plugs feature a platinum pad on the ground electrode for even wear in distributorless ignition systems.

Product Features:

ACTUAL OE or EQUIVALENT DESIGN: OEM quality construction fine wire platinum alloy center electrode provides consistent performance
PLATINUM ALLOY CENTER ELECTRODE: Longer wearing and higher temperature resistance compared to traditional nickel spark plugs
PLATINUM TIP GROUND ELECTRODE: Unless OE specified, platinum protection at the ground electrode provides excellent ignitability and service life
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: Best for vehicles with OE platinum alloy multi-ground electrode plugs

from

$26.84

The Febi Spark Plug Tube is an ideal high quality aftermarket replacement that is manufactured to meet or exceed OE specifications for fit, form, and function.

Product Features:

Engineered to withstand extremes in temperatures
High profile insulation to prevent arching
Premium aftermarket replacement
Provides performance and dependability
Manufactured to meet OE specifications

2004 BMW 645Ci Spark Plugs

More 2004 BMW 645Ci Spark Plugs

Essential 2004 BMW 645Ci Spark Plugs

Autolite Iridium – Iridium XP Finewire Spark Plug: Improved Durability, More Focused Ignition (Part No.XP3924)

Champion – Double Platinum & Power Spark Plug Exceptional Perf OE Replacement RC10PLPB4 (Part No.7436)

Champion – Copper Plus Spark Plug: Dependable Performance, OE Replacement, RC10DMC (Part No.354)

Autolite – Double Platinum Spark Plug: Platinum Firing, Superior Durability, Longer Life (Part No.APP3924)

Bosch – OE Finewire Double Platinum Spark Plug (Part No.F1000306226BOS)

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

NGK – OE Series Standard Nickel Spark Plug: Semi-Surface Discharge Tip Design, BKR6EKUB (Part No.7969)

Motorcraft – MOTOR AND FAN (Part No.SP-485-X)

NGK – Ruthenium HX High Ignitability Spark Plug: DFE Tip Design, FR6AHX-S (Part No.94279)

Motorcraft – SPARK PLUG (Part No.SP-497-X)

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

ACDelco – Rapidfire Spark Plug (Part No.5)

NGK – G-Power Spark Plug: Single Platinum Tip Design, BKR6EGP (Part No.7092)

NGK – OE Series Laser Platinum Spark Plug: Semi-Surface Discharge Tip Design, BKR6EQUP (Part No.3199)

Febi – Febi Spark Plug Tube (Part No.F1012318333FEB)

Popular 2004 BMW 645Ci Spark Plugs Categories

2004 BMW 645Ci Spark Plugs

Spark Plugs Brands To Make Your 2004 BMW 645Ci Last

Popular Champion Spark Plugs

Top 2004 BMW 645Ci Spark Plugs from NGK

FAQs for 2004 BMW 645Ci Spark Plugs

What are the most purchased Spark Plugs for the 2004 BMW 645Ci?

What are the top-rated 2004 BMW 645Ci Spark Plugs?

More Popular Parts for All Makes