X4XZ Ignition Coil & Double Iridium Spark Plug Kit — 4-Coil + 4-Plug for Subaru H4, OEM-Fit

X4XZ UF724 ignition coil and 93501 double iridium spark plug kit replaces four coils and four plugs to restore reliable ignition for select Subaru H4 engines.

If your Subaru Forester (or another compatible Subaru model) is showing signs of misfires, rough idling, or loss of spark, this X4XZ kit bundles four UF724 ignition coils with four 93501 double iridium spark plugs so you can replace the entire ignition set at once. Each component is built to meet or exceed OEM fit and electrical standards, simplifying installation and helping return consistent combustion across all cylinders.

How will replacing all four coils and plugs improve everyday driving?

Swapping out the coils and spark plugs together balances spark delivery and timing across the engine, which often eliminates rough idling, hesitation, and intermittent misfires. Consistent ignition improves throttle response and makes acceleration smoother, especially under load.

• Replaces worn ignition parts that cause backfiring and misfires
• Restores even spark strength to all cylinders
• Helps reduce engine jerking and unstable idle
• Designed for plug-and-play fit to minimize installation time

Which Subaru models and engines are compatible with this kit?

This OEM-style kit fits a range of horizontal 4 (H4) Subaru engines. It’s intended for Forester, Impreza, Legacy, Outback, and XV Crosstrek model years and engine variants listed in the compatibility details. Always verify against your vehicle’s year and engine code before purchase.

• Compatible: 2014–2016 Forester H4 2.5L
• Compatible: 2013–2015 Impreza H4 2.0L; 2013–2014 Legacy/Outback H4 2.5L
• Compatible: 2013–2014 XV Crosstrek H4 2.0L
• See product images for extended vehicle cross-reference

What performance and build features do the UF724 coils and 93501 plugs offer?

The UF724 coils are constructed to match factory electrical outputs and mounting points, while the 93501 double iridium plugs use fine iridium electrodes for consistent spark and longevity. Together they are intended to meet OEM tolerances and provide stable performance under normal driving conditions.

• Double iridium spark plugs for durable, consistent sparking
• Ignition coils built to OEM electrical and fit specifications
• Packaged as a complete 4-coil + 4-plug replacement set
• OE references: UF724 + 93501; replaces UF721, SU003-00417 and others

How easy is installation and what support is included after purchase?

The kit is designed to fit directly into original mounting points and electrical connectors, so a mechanically competent DIYer or a technician can install it without modification. No printed manual is included, but X4XZ provides customer support and a one-year product service period to address fitment or quality questions.

• Plug-and-play design for fast replacement
• No instruction manual included; recommended professional help if unsure
• 24-hour customer service and 1-year product warranty from X4XZ
• Sold as ignition coils x4 and double iridium plugs x4 in one package

Who is this kit for? If you own a compatible Subaru with symptoms like check-engine light, misfire codes, poor idle, or loss of power, and you want an all-in-one replacement set that aligns with OEM specs, this X4XZ UF724 + 93501 kit is tailored for performing a complete ignition refresh. It’s a practical option for DIY maintenance, independent shops, and anyone looking to restore reliable spark function without sourcing coils and plugs separately.