X4XZ Ignition Coil & Double Iridium Spark Plug Kit — 6‑Piece for Nissan/Infiniti 3.5L–4.0L, OE 22448‑AL61C — Direct Fit, Long‑Life

The X4XZ UF401 ignition coil and 4469 double iridium spark plug 6-piece kit replaces worn ignition components to restore smoother starts, steadier idle, and improved throttle response for compatible Nissan and Infiniti engines.

If your vehicle shows signs of misfires, rough idling, or reduced power, replacing neglected coils and plugs can often resolve those issues. This kit includes six ignition coil packs and six double iridium spark plugs designed to meet or exceed original equipment specifications and fit a range of Nissan and Infiniti V6 and V8 applications. Components are built for durability and consistent spark delivery so installation is straightforward and the engine runs more reliably.

Which models and years will this kit fit?

This kit is engineered for many Nissan and Infiniti vehicles with 3.5L and 4.0L engines. It covers popular models across early-2000s to late-2010s model years, but always verify compatibility against your vehicle’s OEM number before purchasing.

• Fits Nissan Altima (2002–2006 3.5L), Maxima (2002–2008 3.5L), 350Z (2003–2006 3.5L).
• Supports Frontier, Pathfinder, Xterra, and NV series with listed years and displacements.
• Includes Infiniti coverage for FX35, G35, M35, I35 and QX4 model years indicated.
• Check the second main product image or OE reference 22448-AL61C to confirm fit.

How do these ignition coils and double iridium spark plugs improve performance?

The coils and iridium plugs are designed to produce steady, reliable sparks across operating conditions. Better high-voltage transfer and a durable iridium tip combine to reduce misfires, improve cold starts, and maintain combustion efficiency over a long service life.

• Double iridium electrodes for extended lifespan and consistent ignition.
• High-quality coil materials and ferrite noise suppression to prevent radio interference.
• Thermoplastic connectors resist heat cycling and reduce connector failures.
• Direct-fit design to simplify installation and match OE electrical characteristics.

What are the quality and durability features of this kit?

Each component is manufactured to meet or improve upon OEM design to deliver reliable operation over many miles. The iridium plugs are rated for long service intervals, while the coils use stainless-steel internals and noise suppression to protect electrical systems.

• Iridium plugs offer long working life—consistent performance up to roughly 100,000 kilometers under normal use.
• Stainless-steel springs and internal ferrite reduce electrical noise and ensure cleaner signal transmission.
• Robust thermoplastic coil connectors resist heat-related cracking and maintain tight connections.
• OE reference numbers included for cross-checking and correct replacement.

What comes in the box and what support is provided?

The package contains six ignition coil packs and six double iridium spark plugs—sufficient to service one cylinder bank or an entire V6/V8 ignition system depending on your vehicle. No printed manual is included, but customer support and a one-year product service are offered if you run into fitment or quality issues.

• Contents: 6 x ignition coils, 6 x double iridium spark plugs (no paper manual).
• OE and replacement cross-reference numbers listed for compatibility checks.
• 24-hour customer service and one-year coverage for product-related concerns.

Who is this for: This X4XZ kit is intended for DIY mechanics and professional technicians who need a complete ignition coil and spark plug replacement for compatible Nissan or Infiniti vehicles. It suits owners dealing with misfires, rough idle, reduced fuel efficiency, or anyone performing scheduled ignition maintenance who wants longer-life plugs and reliable coils that align with OEM specifications.