Parts for your 2015 Subaru Exiga-Ignition coils

2015 Subaru Exiga ignition coils — what they do and when to replace them

Ignition coils are absolutely relevant to the 2015 Subaru Exiga, including the Crossover 7. This model runs a coil-on-plug electronic ignition system with one coil per cylinder. That design is documented in Subaru’s Factory Service Manual for the FB-series engines used in the 2015 Exiga, the Subaru FAST electronic parts catalogue, and major ignition component catalogues from Denso and NGK. So yes — the 2015 Exiga is fitted with ignition coils, and they’re central to smooth running, easy starts, and good fuel economy.

Each coil takes 12-volt battery power and steps it up to a high-voltage spark for its spark plug, timed precisely by the engine control unit. With an individual coil on each cylinder, the Exiga gets strong, consistent spark, better control under load, and fewer misfires than older shared-coil setups.

Coils aren’t a routine “change every service” item, but heat, vibration, moisture, and oil contamination can age them. Best practice is to inspect them whenever the spark plugs are replaced (often around the 100,000 km mark with iridium plugs), and during any diagnosis of a misfire. Look for cracked housings, swollen rubber boots, green/white corrosion on terminals, or oil in the plug tubes from a rocker cover leak. If removing coils, keep them in cylinder order, avoid yanking on the wiring, and use a dab of dielectric grease inside the boots to help sealing and future removal.

• Common signs a coil is on the way out: rough idle, hesitation under load, hard starting, higher fuel use, raw fuel smell, check engine light, and fault codes like P0301–P0304 (cylinder-specific misfires).
• Replacement tips: use quality OEM-spec coils (Subaru/Denso), fix any oil leaks first, and tighten the small coil hold-down bolts only to factory spec — overtightening can crack the coil or cam cover.

There’s no fixed replacement interval, many coils run well past 150,000–200,000 km, but replace any that test weak or show damage. If the vehicle has higher kilometres and multiple coils test marginal, it’s reasonable to refresh the set to restore a crisp spark and avoid repeat visits. After replacement, clear codes, road test, and verify fuel trims and misfire counters are stable.

Worth noting for owners of turbo variants sold in some markets: they also use coil-on-plug ignition. Given the higher under-bonnet temperatures, make sure all heat shields and clips are refitted correctly to protect the coils and harness.

Popular questions about 2015 Subaru Exiga ignition coils

How often should ignition coils be replaced on a 2015 Exiga?
There’s no set kilometre interval. Coils are replaced when they fail testing or show symptoms like misfires or hard starting. Inspect them whenever the spark plugs are changed and during any engine-light diagnosis. Many last well beyond 150,000 km if the engine is leak-free and serviced on time.

Can a failing ignition coil damage other components?
Yes. Persistent misfires can overheat and damage the catalytic converter and may foul the spark plugs. If the Exiga shows a flashing check engine light or strong misfire, avoid extended driving and get it checked promptly.

Are all Exiga coils the same across engines?
No. The 2015 Exiga/Crossover 7 commonly runs FB-series engines, while earlier Exiga models may use EJ-series engines. Both use coil-on-plug, but part numbers and connector styles differ. Always match coils to the vehicle’s VIN/engine code or use OEM-spec references.