2022 Subaru Crosstrek Spark Plug Type and Gap

Quick Reference

Why the Right Plug Matters

Choosing the correct spark plug for your 2022 Subaru Crosstrek is crucial for optimal engine performance, fuel efficiency, and longevity. The "right" plug isn't just about fitment; it's about heat range and electrode material.

• Heat Range: Spark plugs are designed to operate within a specific temperature window. A plug that's too "cold" won't burn off deposits effectively, leading to fouling. A plug that's too "hot" can cause pre-ignition or detonation, which can severely damage engine components. Subaru engineers specify the ideal heat range for the FB20D and FB25D engines to ensure efficient combustion and prevent engine damage.

• Electrode Metal: Modern engines like those in your Crosstrek typically use precious metal plugs due to their extended service intervals and superior performance. Your 2022 Crosstrek comes equipped with iridium spark plugs from the factory. Iridium is an extremely hard and corrosion-resistant metal, allowing for very fine electrodes that produce a stronger, more consistent spark. This translates to better fuel economy and reduced emissions over a longer period compared to traditional copper or even platinum plugs.

  • Iridium: Standard in your Crosstrek, offering excellent longevity (60,000 miles is typical) and performance due to the fine wire electrode.
  • Platinum: While superior to copper, platinum plugs have a shorter lifespan than iridium and may not be the OEM specified plug for your vehicle. Using them might shorten your replacement interval.
  • Copper: Not recommended for your Crosstrek. Copper plugs have a much shorter lifespan and cannot withstand the operating conditions or extended service intervals of modern engines.

How to Gap a Spark Plug

While most iridium plugs come pre-gapped, it's always a good practice to double-check the gap before installation. However, be extremely careful when gapping iridium plugs due to their delicate fine-wire electrodes.

1. Obtain a Wire-Type Gap Gauge: This is the most accurate tool for measuring spark plug gap.
2. Measure the Gap: Carefully slide the appropriate wire gauge (0.044 inches or 1.1 mm for your Crosstrek) between the center and ground electrodes. There should be a slight drag.
3. Adjust if Necessary (with extreme caution): If the gap is incorrect, gently bend the ground electrode only. Never try to bend or adjust the delicate center iridium electrode. For iridium plugs, it's often best to return a wrongly gapped plug rather than risk damaging it.

Replacement Procedure Tips for Boxer Engines

Replacing spark plugs on a Subaru Crosstrek with a Boxer engine can be more challenging than on an inline or V-engine due to the horizontally opposed cylinder layout. Patience and the right tools are key.

1. Access: The spark plugs are located on the sides of the engine, under the coil packs. You may need to remove the airbox or other components on one or both sides to gain adequate access.
2. Coil-on-Plug Removal: Each spark plug has a dedicated coil pack. Carefully disconnect the electrical connector by pressing the tab and pulling. Then, gently twist and pull the coil pack straight up to remove it from the spark plug. Avoid yanking on the wires.
3. Spark Plug Socket: Use a dedicated spark plug socket (typically 14mm for your Crosstrek's iridium plugs) with a rubber insert to protect the porcelain and help hold the plug during removal and installation. A universal joint or wobble extension can be very helpful for navigating the tight spaces.
4. Anti-Seize Debate: There is ongoing debate about using anti-seize on spark plug threads. Most modern spark plugs, especially those from NGK and Denso, have a special coating on the threads that acts as anti-seize. Applying additional anti-seize can potentially alter the torque readings, leading to over-tightening. Follow the spark plug manufacturer's recommendations. If they don't recommend it, don't use it. For your 2022 Crosstrek, with modern plugs, it's generally advised not to use anti-seize.
5. Dielectric Grease: Apply a small amount of dielectric grease inside the spark plug boot (the part that connects to the top of the spark plug). This helps seal out moisture, prevents corrosion, and makes future removal easier.
6. Torque is Crucial: Always use a torque wrench to tighten the new spark plugs to the specified 15.0 lb-ft (20.0 Nm). Over-tightening can strip threads or crack the cylinder head; under-tightening can lead to plugs backing out or causing misfires.

Known Issues (Not Applicable for 2022 Crosstrek)

Fortunately, the 2022 Subaru Crosstrek's FB20D and FB25D engines do not have widespread "known issues" related to spark plugs, such as the two-piece plug breakage seen in some older Ford 3-valve engines or unique ionization-sensing coil systems like some GM 5.3L engines. As long as you use the correct OEM or equivalent iridium plugs and follow the recommended replacement interval, you should experience trouble-free operation.

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