NGK LFR6AIX-11 6619 Iridium IX Spark Plugs – Pack of 6 | OEM Replacement

NGK LFR6AIX-11 (6619) Iridium IX Spark Plug – Pack of 6
Premium Iridium Spark Plugs for Nissan, Infiniti & Subaru

Upgrade your ignition performance with the NGK LFR6AIX-11 6619 Iridium IX Spark Plug Pack of 6. Featuring advanced iridium technology, these plugs deliver superior durability, consistent firing, and improved throttle response.

Features & Benefits:

• OEM-quality NGK spark plugs for guaranteed fit and reliability
• Fine iridium tip for long life and high performance
• Faster starts, smooth idling, and better fuel efficiency
• Resistant to fouling and wear for long-lasting use
• Trusted by professional mechanics and enthusiasts worldwide

Vehicle Compatibility:
Commonly fits a wide range of vehicles, including:

• Nissan 350Z, Altima, Maxima, Murano
• Infiniti G35, FX35
• Subaru WRX, Forester, Legacy (select models)
• Mitsubishi Lancer Evolution, Outlander

Check your owner's manual or OEM part number for exact fitment.

Cross Reference:
Denso 5344 (IK16) | Champion REC10WMPB4 | Autolite XP3923 | Bosch 4417

What's Included: 6x Genuine NGK LFR6AIX-11 6619 Iridium IX Spark Plugs

Why Buy From Us:
🔧 100% Genuine NGK Products | 🚗 Perfect Fit for OEM Replacement | 🚀 Fast USA Shipping & Easy Returns

❓ Quick FAQ

What makes iridium better than copper or platinum?
Iridium's extreme melting point allows an ultra-fine 0.6mm electrode tip, requiring less voltage for a hotter, more concentrated spark — resulting in quicker starts and better fouling resistance. These plugs last 40,000–50,000 miles vs. 30,000 for copper.

What does "LFR6AIX-11" mean?
LF = 14mm thread, long reach; R = resistor type (reduces RFI); 6 = mid-range heat rating; IX = Iridium IX construction; -11 = factory-preset 1.1mm gap optimized for coil-on-plug ignition systems.

How do I install these plugs safely?

1. Disconnect the battery, remove the coil packs, and blow debris out of the plug wells.
2. If checking the gap, use a wire loop or feeler gauge — never a coin-style tool, which can snap the delicate tip.
3. Remove the old plugs with a dedicated spark plug socket, keeping the extension straight to avoid cracking the insulator.
4. Hand-thread the new plug in for 4–5 turns to avoid cross-threading the aluminum head — never use anti-seize or a power tool to start it.
5. Torque to 15–22 lb-ft, or hand-tighten plus an additional 1/2–2/3 turn if no torque wrench is available.
6. Reinstall the coil packs, reconnect the battery, and start the engine to confirm a smooth idle.