{"product_id":"ngk-iridium-ix-spark-plug-cr9eix-4-pack-direct-fit-oem-replacement-long-life-iridium-electrode","title":"NGK Iridium IX Spark Plug CR9EIX 4-Pack — Direct-Fit OEM Replacement, Long-Life Iridium Electrode","description":"\u003cp\u003e\u003cstrong\u003eThe NGK CR9EIX Iridium IX spark plug (OEM part 3521) is a high-performance replacement designed to deliver reliable ignition, improved throttle response, and long service life in compatible engines.\u003c\/strong\u003e\u003c\/p\u003e\n\n\u003cp\u003eChoose this genuine NGK OEM replacement when you need a direct-fit spark plug that maintains factory specifications. The CR9EIX Iridium IX uses a fine iridium center electrode and NGK’s precision manufacturing to support consistent combustion and reduced electrode wear. Sold as a 4-pack, this item is ideal for multi-cylinder tune-ups or keeping a spare set on hand.\u003c\/p\u003e\n\n\u003ch3\u003eHow does the CR9EIX improve ignition performance?\u003c\/h3\u003e\n\u003cp\u003eThe iridium center electrode and optimized ground electrode geometry lower the voltage required to fire the plug and focus the spark energy where it’s most effective. This helps create a stronger, more consistent spark across varying engine loads and rpm ranges.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eFine iridium tip for higher melting point and stable sparking\u003c\/li\u003e\n  \u003cli\u003eConsistent spark gap maintained by precise manufacturing\u003c\/li\u003e\n  \u003cli\u003eReduced misfire risk under normal operating conditions\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWill these plugs fit my vehicle and replace OEM parts?\u003c\/h3\u003e\n\u003cp\u003eYes — this is an OEM-equivalent part with NGK part number 3521, meant to replace factory-specified plugs that call for CR9EIX. Always check your vehicle’s service manual or parts list to confirm compatibility before ordering.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eNGK OEM part #3521 confirms direct-fit replacement status\u003c\/li\u003e\n  \u003cli\u003eThread size, reach, and heat range match factory specs for compatible models\u003c\/li\u003e\n  \u003cli\u003eSold in a 4-pack for multi-cylinder engines or maintenance kits\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow long can I expect these spark plugs to last?\u003c\/h3\u003e\n\u003cp\u003eIridium plugs typically outlast standard copper or platinum plugs because iridium is more wear-resistant. Actual longevity depends on driving conditions and engine health, but many users experience extended service intervals compared with conventional plugs.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eDurable iridium electrode resists erosion over time\u003c\/li\u003e\n  \u003cli\u003eMaintains stable gap longer, reducing early replacement frequency\u003c\/li\u003e\n  \u003cli\u003ePerformance longevity can help preserve fuel efficiency and throttle response\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eWhat should I know about installation and maintenance?\u003c\/h3\u003e\n\u003cp\u003eInstallation follows typical spark plug replacement steps: verify gap (if required), hand-start threads to avoid cross-threading, and torque to the manufacturer’s specification. Use anti-seize only if the vehicle maker recommends it and re-check torque after initial heat cycles.\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003eCheck vehicle manual for correct torque and gap values\u003c\/li\u003e\n  \u003cli\u003eStart threads by hand to prevent damage to cylinder head\u003c\/li\u003e\n  \u003cli\u003eInspect ignition boots and wires\/coils when replacing plugs\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eWho this is for: Mechanics, car enthusiasts, and DIY owners who want a genuine NGK OEM replacement for reliable ignition and longer service intervals. The CR9EIX Iridium IX 4-pack is suited to drivers who need factory-fit parts for routine maintenance, performance-oriented replacements, or multi-cylinder tune-ups. If you prioritize consistent starting, steady throttle response, and reduced spark plug change frequency while using a trusted OEM brand, this NGK plug is a practical choice.\u003c\/p\u003e\n\u003csection class=\"product-faq-snippet\"\u003e\u003ch3\u003eFAQ\u003c\/h3\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: Is the CR9EIX an OEM replacement and what is the part number?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: Yes. This NGK CR9EIX is an OEM-equivalent replacement listed as NGK part number 3521.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"faq-item\"\u003e\n\u003cp class=\"faq-q\"\u003eQ: How many plugs are included and are they pre-gapped?\u003c\/p\u003e\n\u003cp class=\"faq-a\"\u003eA: This listing includes a 4-pack. Verify and adjust gap per your vehicle’s specifications before installation.\u003c\/p\u003e\n\u003c\/div\u003e\u003c\/section\u003e","brand":"NGK","offers":[{"title":"Default Title","offer_id":48083133726878,"sku":"B004SKYAWM","price":62.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0781\/2041\/9486\/files\/ngk-cr9eix-front-packaging.jpg?v=1785825912","url":"https:\/\/northtrailauto.ca\/products\/ngk-iridium-ix-spark-plug-cr9eix-4-pack-direct-fit-oem-replacement-long-life-iridium-electrode","provider":"North Trail Auto","version":"1.0","type":"link"}