Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2018 Subaru WRX STIFACTORY OEM SERVICE PROCEDURE
Engine Ignition System (STI): General Description: Specification
- Except for TYPE RAENGINE IGNITION SYSTEM (EXCEPT FOR TYPE RA) SPECIFICATION
Item Specifications Ignition coil Type FK0368 Ignition system Independent ignition coil Manufacturer Diamond Electric Spark plug Manufacturer and type NGK: SILFR6A Thread size (diameter, pitch, length) mm 14, 1.25, 26.5 Spark plug gap mm (in) Standard 0.7 - 0.8 (0.028 - 0.031) Electrode Center electrode: Iridium
Ground electrode: Platinum - TYPE RAENGINE IGNITION SYSTEM (TYPE RA) SPECIFICATION
Item Specifications Ignition coil Type FK0368 Ignition system Independent ignition coil Manufacturer Diamond Electric Spark plug Manufacturer and type NGK: ILFR7H Thread size (diameter, pitch, length) mm 14, 1.25, 26.5 Spark plug gap mm (in) Standard 0.5 - 0.6 (0.019 - 0.023) Electrode Center electrode: Iridium
Ground electrode: Platinum
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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