Parts for your 2022 Mitsubishi Asx-Oxygen sensor

2022 Mitsubishi ASX oxygen sensor — what it does and when to replace it

Yes, the 2022 Mitsubishi ASX runs oxygen sensors. Technical documentation for the ASX/RVR platform shows a front air–fuel ratio (wideband) sensor and a rear heated oxygen sensor in the exhaust stream. Mitsubishi workshop manuals for the 4B11 2.0‑litre petrol list both sensors, the Mitsubishi ASA parts catalogue carries front A/F and rear O2 sensor part lines for 2022 VINs, and ADR 79/04 (Euro 5/6) emissions and OBD-II requirements (SAE J1979) mandate upstream and downstream lambda sensing on petrol engines with a three-way catalytic converter. So, oxygen sensors are absolutely relevant on this model.

On the 2022 ASX, the front wideband sensor constantly feeds the ECU with real-time mixture data so it can hold the engine near stoichiometric for smooth running and minimal fuel burn. The rear sensor sits after the catalytic converter and checks the cat is doing its job, it also helps the ECU fine-tune long-term fuel trims. Healthy sensors mean better economy, crisp throttle response, and easier WOF/rego emissions checks.

They’re not a fixed-interval replacement item in the factory service schedule, but by 150,000–200,000 km many will have slowed down enough to hurt economy and trigger a Check Engine Light. Consider testing or replacing sooner if the ASX shows these signs:

• Noticeable jump in fuel use, rich exhaust smell, or sooty tailpipe
• Rough idle, hesitation, or lazy throttle response
• CEL with codes like P0134, P0137, P0141, P015A–P015D, or P0420

Good practice during servicing:

1. Scan live data, look for slow or stuck sensor responses and excessive fuel trims.
2. Inspect wiring and connectors first — heat and road grime can cause intermittent faults.
3. Fix exhaust leaks before and after the cat, leaks skew readings.
4. When replacing, use quality OEM-equivalent sensors (Denso/NTK are common on Mitsubishi). Most come pre-coated with anti-seize, if so, don’t add more. Typical install torque is in the 35–45 N·m range — check the service manual for your exact engine code.
5. Avoid touching the sensing tip, route the harness away from the exhaust, and clear codes. A short drive cycle will let the ECU relearn trims.

Look after the oxygen sensors and the 2.0‑litre MIVEC in the ASX will keep running sweet, sipping less fuel and keeping emissions in check.

How many oxygen sensors does a 2022 Mitsubishi ASX have?

Most 2022 ASX 2.0‑litre petrol models have two: a front wideband air–fuel ratio sensor before the catalytic converter and a rear heated oxygen sensor after it. Some markets and trims may vary, but two is the common setup.

What’s a reasonable replacement interval?

There’s no set interval in the factory schedule. If there’s no fault code and economy is on target, leave them be. Many technicians start testing or pre-emptively replacing around 150,000–200,000 km, especially if fuel use has crept up.

Can a tired oxygen sensor damage the catalytic converter?

Yes. A lazy front sensor can cause rich running, which overheats and poisons the cat. Catching faulty sensors early helps protect the catalyst and saves money down the track.