Parts for your 2018 Mitsubishi Asx-Knock sensor

2018 Mitsubishi ASX Knock Sensor — What It Does and When to Sort It

Yes, the 2018 Mitsubishi ASX does use a knock sensor. This isn’t guesswork: the Mitsubishi Motors workshop manual for the ASX/RVR (GA2W/GA3W) with the 2.0L 4B11 engine includes a dedicated Knock Sensor (KS) circuit and diagnostic routines (DTCs P0325, P0326, P0327, P0328). The Mitsubishi ASA electronic parts catalogue also lists a “Knock Sensor” mounted to the cylinder block for this model/engine. Even the official diagnostic sections show wiring diagrams and test procedures for the KS, confirming it’s fitted and monitored by the ECU.

On the 2018 ASX, the knock sensor is a clever little microphone bolted to the engine block. It listens for high-frequency vibrations from detonation (pinging) and tells the ECU to tweak ignition timing on the fly. That helps protect the engine from damage, smooths out performance on our Aussie and Kiwi fuels, and lets the car adapt whether you’re running 91 RON or stepping up to 95/98.

If the knock sensor goes crook, the dash may light up with a Check Engine warning and store codes like P0325. Drivers might notice dull performance, higher fuel use, or pinging under load. The ECU often plays it safe by retarding timing, so it’ll feel a bit flat.

• Servicing approach: it’s not a routine replacement item. Treat it like a “fit and forget” sensor unless there’s a fault code, obvious pinging, or wiring damage.
• Good habits: use quality petrol, keep up with regular servicing, and sort any intake/exhaust leaks that can confuse engine noise detection.
• Inspection: check the harness and connector under the bonnet for heat or oil contamination. A poor ground or brittle wiring can trigger KS codes.
• Replacement tips: only fit a quality, correct-spec sensor. Mount it clean against the block, torqued to the factory spec (don’t overtighten, no sealant or thread tape). After replacement, clear codes and let the ECU relearn with a proper warm-up drive.
• When to book it in: persistent pinging, repeated KS fault codes, or a Check Engine light tied to P0325–P0328 is the cue for diagnosis.

For ASX owners across Australia and New Zealand, the knock sensor is a quiet achiever. Keep the wiring happy, run the right fuel, and it’ll keep the timing optimised and the engine safe for the long haul.

FAQs — 2018 Mitsubishi ASX Knock Sensor

Where is the knock sensor on a 2018 ASX?
It’s bolted to the engine block, typically on the intake side beneath the manifold on the 2.0L 4B11. Access can be tight from up top, many techs go in from under the vehicle or remove related components for room.

Is it safe to drive with a bad knock sensor?
You can usually drive short term, but it’s not ideal. The ECU may pull timing to protect the engine, which dents performance and burns more fuel. Sort the fault promptly to avoid long-term issues.

Do I need 95/98, or is 91 RON fine?
The 2018 ASX is designed for 91 RON minimum. The knock sensor and ECU adjust timing to suit, but using higher octane can help under heavy loads or hot conditions. If you hear pinging on 91, get it checked rather than masking a problem with premium fuel.