X4XZ Ignition Coil & Double Iridium Spark Plug Kit, 4-Pack UF507/4503 — OEM Fit, Long-Life

X4XZ UF507 ignition coils paired with 4503 double iridium spark plugs provide a direct-fit replacement set designed to restore reliable spark, smoother idling, and consistent engine performance for many Lexus and Toyota models.

When an ignition coil or spark plug starts to fail, symptoms like misfires, rough idle, or reduced fuel efficiency become noticeable. This X4XZ kit includes four UF507 ignition coil packs and four 4503 double iridium spark plugs engineered to match or improve on original equipment specifications, simplifying installation while aiming to improve starting consistency and long-term durability.

How do these ignition coils and spark plugs improve engine performance?

The ignition coils deliver high-voltage current to the spark plugs reliably, while the double iridium plugs sustain a focused, stable spark for a longer service life. Together they help reduce misfires and support smoother combustion without complex tuning.

• UF507 coils engineered to OEM fit and electrical output.
• Double iridium electrodes for consistent spark and extended life (up to 100,000 km under ideal conditions).
• Improved resistance to heat and electrical noise for dependable firing.

Which vehicles are compatible with this X4XZ kit?

This set is made to replace part numbers UF587/UF630 and is compatible with a wide range of Lexus, Toyota and Scion vehicles. Always cross-check your vehicle’s year and engine before purchasing; see the detailed compatibility list provided with the product images.

• Lexus models: ES, GS, IS, LS, RX, GX, LX, NX, RC and others listed for 2006–2021 model years.
• Toyota models: Camry, 4Runner, Avalon, Tundra, Sequoia, Land Cruiser, RAV4, Highlander, Venza and more (2010–2022 ranges).
• Scion TC compatibility for 2011–2016 shown in the vehicle list.

What are the key build and reliability features to expect?

The sparks plugs use double iridium tips for longer life and steady ignition, while the coils employ thermoplastic connectors, stainless-steel springs, and a ferrite noise suppressor to maintain electrical integrity. Materials and design choices reduce radio-frequency interference and resist heat-related fatigue.

• Ferrite noise suppressor to limit radio interference with electronics.
• Thermoplastic coil connector reduces crack risk from heat cycling.
• Stainless-steel spring ensures solid conductor contact and durability.

How easy is installation and what’s included in the package?

The kit is supplied as a direct-replacement package with four ignition coils and four double iridium spark plugs, matching the OEM form and mounting points for fast swap-out. No printed instruction manual is included, but the parts are plug-and-play for anyone comfortable with basic engine maintenance.

• Included: 4 x UF507 ignition coils and 4 x 4503 double iridium spark plugs.
• Replaces OE numbers like UF587, UF630, LFR5AGP, and several 90919/91919 references.
• Recommended: mechanic or experienced DIYer; basic hand tools required.

Who this is for: This X4XZ UF507 + 4503 kit is suitable for owners of compatible Lexus, Toyota, and Scion vehicles who need a reliable, long-life ignition coil and spark plug replacement without upgrading engine management. It’s ideal for drivers seeking OEM-fit parts that prioritize consistent starting, reduced misfires, and extended spark-plug service intervals, and for technicians performing scheduled maintenance or addressing ignition-related drivability issues.