BDFHYK Ignition Coil Pack UF401 and Iridium Spark Plugs NGK4469, Fits Nissan 350Z Altima Frontier 3.5L 4.0L V6, Set of 6

UF401 Ignition Coil & 4469 Iridium IX Spark Plug Kit for Nissan / INFINITI V6

Misfire, rough idle, hard starting, cold-start shaking, or hesitation during acceleration can involve worn ignition components, but wiring, injectors, fuel delivery, intake leaks, sensors, compression, and mechanical faults can create similar symptoms. This BDFHYK UF401 ignition coil and 4469 / LFR5AIX-11 spark plug kit is intended for the listed applications below. Confirm the exact vehicle, engine, connector, and reference numbers before ordering.

UF401 / 4469 / LFR5AIX-11 Vehicle Fitment

• Nissan 350Z 2003–2006, Altima 2002–2006, Maxima 2002–2008 and Quest 2004–2009 — 3.5L V6
• Nissan Frontier 2005–2019, Xterra 2005–2015, Pathfinder 2005–2012 and NV1500/NV2500/NV3500 2012–2019 — 4.0L V6
• INFINITI FX35 2003–2008, I35 2002–2005, QX4 2002–2003, G35 2003–2007 and M35 2006–2008 — 3.5L V6

What Is Included?

• 6 ignition coils
• 6 Iridium IX spark plugs

UF401 Ignition Coil Reference Numbers

UF401, IC521, GN10246, C1439, 5C1430, IGC0007, 52-1774, 22448-AL61, 22448-AL61C

When Should You Inspect the Ignition Coils?

Ignition coils do not have a universal mileage-based replacement interval. A practical time to inspect them is when the spark plugs are due, when the vehicle reaches higher-mileage service, or when symptoms appear. On an older vehicle with roughly 60,000–100,000+ miles and unknown ignition-service history, inspect the coil boots, connectors, plug wells, spark plug wear, and stored misfire codes rather than replacing coils by mileage alone.

Frequent short trips, stop-and-go driving, high-load use, long idling, heat cycling, or oil and moisture in the plug wells can justify earlier inspection. Worn spark plugs can also increase the voltage demand placed on the ignition coils.

What May Improve After Replacing a Confirmed Weak Coil or Worn Plug?

• More stable idle when an ignition fault was causing rough running
• Easier, more consistent starting when weak spark was part of the problem
• More consistent acceleration and load response when misfire or hesitation came from the ignition system
• Fewer cylinder-specific misfire events after the actual failed component is corrected

These are restoration benefits, not a promise of extra horsepower or guaranteed fuel-economy gains. If the engine still misfires, continue diagnosis instead of replacing more parts at random.

High-Mileage Ignition Service Scenarios

Spark Plug Service Is Due

When spark plugs are being serviced, inspect the ignition coils at the same time for cracked housings, carbon tracking, damaged boots, loose connectors, oil contamination, or moisture. Replace coils only when testing or physical condition supports replacement.

Cold-Start Shaking or Rough Idle

Check for cylinder-specific misfire codes and inspect the plug and coil on the affected cylinder. A flashing check-engine light can indicate an active misfire and should be addressed promptly because continued misfiring can damage the catalytic converter.

Hesitation Under Acceleration or Load

A weak coil or worn plug may become more noticeable when cylinder pressure rises under acceleration. Confirm the affected cylinder and compare the original coil and plug references before replacement.

Fitment & Installation Checks

• Match the exact year, make, model, engine, and cylinder configuration.
• Compare connector keying, coil body, mounting point, boot profile, and printed reference numbers.
• Confirm spark plug reference 4469 / LFR5AIX-11 for the exact engine.
• Follow the vehicle manufacturer's spark plug gap and tightening-torque specification; do not guess.
• Inspect wiring, connectors, boots, and plug wells for oil, moisture, corrosion, or physical damage.

Important: These are BDFHYK OE-style aftermarket ignition service components, not factory-branded parts. A diagnostic trouble code alone does not prove that an ignition coil has failed.