DENSO Iridium Spark Plug 3478 FXU16HR11, original part number 1822A088 high-life upgrade.

Denso iridium spark plug FXU16HR11 (OEM number 1822A088) designed for longevity-focused models, using iridium electrode material; superior high-temperature resistance and corrosion resistance compared to nickel alloy plugs; electrode wear is very slow; lifespan 80,000–100,000 km; high-longevity upgrade. Fits Denso brand vehicles from 2000 onward; verify thread size M14x1.25 and reach 26.5 mm. Function: iridium fine- gap electrode provides more stable ignition energy, reduces misfire, improves combustion efficiency. Installation difficulty is medium; torque with a torque wrench to standard specification.