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 Crosstrek Base, Automatic CVT TransFACTORY OEM SERVICE PROCEDURE
Front Oxygen (A/F) Sensor: Installation
CAUTION:
If lubricant is spilt over the exhaust pipe, wipe it off with cloth to avoid emission of smoke or causing a fire.
- Before installing front oxygen (A/F) sensor, apply anti-seize compound only to the threaded portion of front oxygen (A/F) sensor to make the next removal easier.CAUTION: Never apply anti-seize compound to the protector of front oxygen (A/F) sensor.
Anti-seize compound:
NEVER-SEEZ NSN, JET LUBE SS-30 or equivalent
- Install the front oxygen (A/F) sensor, and connect the front oxygen (A/F) sensor connector.
Tightening torque:
21 N.m (2.1kgf-m, 15.5ft-lb)
- Install the under cover. Ref. to EXTERIOR/INTERIOR TRIM>Front Under Cover>INSTALLATION .
- Lower the vehicle.
- Connect the battery ground terminal. Ref. to REPAIR CONTENTS>NOTE>BATTERY .
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.