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

Execution Condition

Secondary parameters	Execution condition
(1), (2) and (3)
Battery voltage	≥ 6V
(4)
Battery voltage Main throttle position	≥ 6V < Value from Map
(5)
Battery voltage Main throttle position	≥ 6V ≥ Value from Map

BATTERY VOLTAGE SPECIFICATION - MAP

Battery voltage	7.5V	8V
Main throttle position	27.5°	31°

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.