Denso Iridium Long Life Spark Plugs SK16R11 (3324) — 4‑Pack, Durable Iridium Tips for Stable Ignition

DENSO SK16R11 Iridium Long Life spark plugs — a genuine 4-pack replacement designed to restore reliable ignition performance and extended service life.

These DENSO 3324 (SK16R11) iridium spark plugs come as an authentic four-piece set intended for direct-fit replacement in compatible engines. Built using DENSO’s iridium tip technology and manufactured to original-equipment specifications, they offer consistent spark delivery and corrosion-resistant construction. The package includes original packaging and the correct hardware to simplify installation; always verify vehicle compatibility with your fitment tool before purchase.

How do these spark plugs improve ignition reliability?

Denso’s iridium tip provides a precise, durable electrode that requires less voltage to fire and resists wear compared with standard nickel plugs. That steadier spark timing helps maintain smooth starts and consistent combustion across operating conditions.

• Fine iridium center electrode for consistent spark formation
• Corrosion-resistant materials to preserve contact quality
• Stable gap retention reduces misfires over time

Will these plugs fit my vehicle and how do I confirm compatibility?

The SKU SK16R11 corresponds to DENSO part number 3324 and fits vehicles specified by that OE cross-reference. Compatibility depends on make, model, engine code and year, so check your vehicle’s service manual or use the retailer’s fitment/vehicle compatibility tool before ordering.

• Part number: DENSO 3324 (SK16R11)
• Sold as a 4-piece genuine DENSO replacement pack
• Confirm fitment via online fitment tool or dealer reference

How long can I expect these iridium plugs to last?

Iridium electrodes typically outlast conventional plugs due to their hardness and higher melting point, giving longer service intervals under normal driving conditions. Actual lifespan depends on driving habits, engine condition, and maintenance, but iridium plugs commonly provide extended mileage before a replacement is needed.

• Durable iridium tip for extended service life
• Better gap stability compared with standard plugs
• Replace according to vehicle manufacturer guidelines

What comes in the package and is installation straightforward?

This listing contains a genuine DENSO four-pack (4 PCS) of SK16R11 spark plugs, shipped in original packaging with necessary hardware. Installation is direct-replacement for compatible engines; basic hand tools and torque specifications are required, or have a qualified technician perform the swap if unsure.

• Includes four DENSO 3324 (SK16R11) spark plugs in original packaging
• Includes required sealing/insulator hardware when applicable
• Direct replacement — follow torque specs and gap settings

Who is this for: This DENSO 4-pack is aimed at vehicle owners and professional mechanics seeking authentic OEM-quality iridium spark plugs for routine maintenance or performance restoration. It’s suitable for drivers who prefer longer service intervals and consistent ignition performance, and for anyone replacing all cylinders during a tune-up to maintain even combustion across the engine.