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.
2016 Subaru WRX BaseFACTORY OEM SERVICE PROCEDURE
Rear Oxygen 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 rear oxygen sensor, apply the anti-seize compound only to the threaded portion of rear oxygen sensor to make the next removal easier.CAUTION: Never apply anti-seize compound to the protector of rear oxygen sensor.
Anti-seize compound:
NEVER-SEEZ NSN, JET LUBE SS-30 or equivalent
- Install the rear oxygen sensor.
Tightening torque:
30 N.m (3.1 kgf-m, 22.1 ft-lb)
- Connect the rear oxygen sensor connector to the engine harness.
- Install the under cover. < Ref. to INSTALLATION , Front Under Cover. >
- Lower the vehicle.
- Connect the ground terminal to battery sensor. < Ref. to BATTERY , NOTE, Notes. >
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
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.