Parts for your 2016 Subaru Exiga-Oxygen sensor

2016 Subaru Exiga oxygen sensor: what it does and when to replace it

Yes, the 2016 Subaru Exiga (including the Japan‑market Crossover 7 variant) is fitted with oxygen sensors. More precisely, it uses a front air–fuel ratio (A/F) sensor upstream of the catalytic converter and a rear oxygen sensor downstream. This layout is documented in Subaru’s Global Service Manual for the YA Exiga/Crossover 7 engine control system (EC section), which details the A/F sensor and rear O2 sensor circuits and diagnostics, and is corroborated by the Subaru FAST electronic parts catalogue for YA-series Exiga models listing “Sensor complete – air fuel ratio” and “Sensor complete – oxygen.” Aftermarket parts catalogues (e.g., DENSO) also list the corresponding sensors for 2016 Exiga engines, reflecting standard OBD/JOBD emissions control that relies on both sensors to manage fuelling and monitor catalyst efficiency.

On this Exiga, the front A/F sensor constantly measures the exhaust’s oxygen content to let the ECU trim fuelling with fine precision. That’s how it keeps the mix spot‑on for smooth running, good power, and tidy emissions. The rear oxygen sensor sits after the cat to check the converter is doing its job, if its readings aren’t right compared with the front sensor, the ECU can flag a fault and protect the environment – and the wallet – by prompting a fix before things snowball.

There’s no hard-and-fast replacement interval, but these sensors are wear items. By around 160,000–200,000 kilometres, they can slow down or drift, causing higher fuel use, rough idle, or a Check Engine Light with codes like P0130–P0161. As part of servicing, it’s smart to:

• Scan live data for fuel trims and sensor response, look for lazy switching or odd trims.
• Inspect the harness and connectors for heat damage or oil contamination under the bonnet.
• Address any exhaust leaks before or near the sensors – leaks can skew readings.

If replacement’s on the cards, use genuine Subaru or quality OEM‑equivalent (often DENSO) sensors matched to the engine code. The front unit is a wideband A/F sensor – don’t swap it with a simple narrowband. Apply only the manufacturer’s pre‑applied anti‑seize if present, adding extra can foul the element. Tighten to the spec in the Subaru service manual (commonly in the mid‑40 N·m range, but check for your exact engine). A slightly warm exhaust can help removal, but watch for burns. After fitting, clear codes, perform an idle relearn if required, and recheck fuel trims on a road test. That keeps the Exiga sipping fuel, passing emissions, and running sweet.

Popular questions

How many oxygen sensors does a 2016 Subaru Exiga have?
Most 2016 Exiga/Crossover 7 models run two: a front air–fuel ratio (A/F) sensor before the catalytic converter and a rear oxygen sensor after it. This setup lets the ECU control fuelling precisely and verify catalyst performance.

What are the symptoms of a failing oxygen sensor on an Exiga?
Common clues include increased fuel consumption, rough idle, hesitation, and a Check Engine Light. Scan tools may show slow sensor response, abnormal fuel trims, or codes such as P0130–P0161. Fix exhaust leaks and wiring issues first, then replace sensors as needed.

Do both sensors need replacing at the same time?
Not necessarily. Replace the sensor that’s failed diagnostics. That said, if the vehicle has high kilometres and the other sensor is original, many techs proactively replace both to keep fuelling and catalyst monitoring consistent.