Parts for your 2014 Mitsubishi Asx-Knock sensor

2014 Mitsubishi ASX knock sensor — what it does and when to sort it

Based on factory material — including the Mitsubishi RVR/ASX Workshop Manual (2010–2016, Engine/ECM sections) and service information covering the 4B11 2.0L MIVEC engine — the 2014 Mitsubishi ASX petrol models are fitted with a block-mounted knock sensor and support OBD-II knock sensor fault codes (e.g., P0325 range/circuit). The same sensor is referenced in Mitsubishi wiring diagrams for the ASX/Outlander Sport/Lancer using the 4B1 engine family. Diesel variants in some markets use different combustion control strategies and typically won’t rely on a conventional knock sensor for detonation control, but the common AU/NZ 2.0L petrol ASX definitely has one on the engine block.

The knock sensor’s job is simple but vital: it listens for high-frequency vibrations (knock/ping) and tells the ECU to tweak ignition timing on the fly. That keeps performance smooth, protects pistons and bearings, and helps maintain decent fuel economy on our varied Aussie and Kiwi fuels. It’s a fit‑and‑forget part for most of its life, but heat, age, or wiring issues can make it go grumpy.

When it’s playing up, the ASX may light the check engine lamp, set a knock sensor fault code (often P0325), feel a bit doughy under load, or ping on hills. Before swapping parts, it’s smart to check the basics: fresh petrol, no intake or vacuum leaks, and good engine earths. A scan tool that reads live data and freeze‑frame will save time.

• Location: typically bolted to the engine block beneath the intake side, around the middle cylinders, with a single electrical connector.
• Service tip: the sensor must sit on a clean, flat, oil‑free pad on the block. Fit it with the factory torque spec — over‑ or under‑tightening can skew readings.
• Wiring: inspect the harness carefully. A damaged shielded wire or loose connector is a common culprit.
• Replacement: only replace when diagnosed faulty. Use a quality OEM‑equivalent sensor and clear codes after installation, then road test under light and heavy load.

There’s no scheduled replacement interval for the ASX knock sensor, it’s replaced on condition. If the car has done big kilometres, has had an engine-out job, or shows intermittent knock faults, proactive inspection under the bonnet is worthwhile. After fitting, a quick ECU relearn/drive cycle helps the timing maps settle, and the ASX should get its pep back without the risk of knock.

Popular questions about the 2014 Mitsubishi ASX knock sensor

Where is the knock sensor on a 2014 ASX?
On the 2.0L petrol ASX, it’s mounted to the engine block on the intake side, roughly mid‑block near cylinders 2–3. Access is usually from above after moving the intake ducting, or from underneath on a hoist for more room. Look for a small, round sensor with one bolt and a single plug.

What are the signs of a failing knock sensor?
Common giveaways include a check engine light with a knock sensor code (often P0325), lacklustre performance, higher fuel use, and occasional pinging under load. Sometimes the ECU will pull timing as a safety move, so it can feel flat even without obvious noise.

Is it okay to keep driving with a bad knock sensor?
It’ll usually run, but it’s not a great idea. The ECU may default to conservative timing, which saps power and can increase fuel consumption. If genuine knock is present and the sensor can’t report it properly, long‑term engine damage is possible. Best to diagnose and fix it promptly.