Parts for your 2015 Toyota Mark x-Knock sensor

2015 Toyota Mark X knock sensor — purpose, care, and when to replace

Based on technical sources, the 2015 Toyota Mark X is fitted with knock sensors. Toyota’s repair literature for the GRX130 series (Engine Control section) lists DTCs P0325 and P0330 for Knock Sensor 1 and Knock Sensor 2, and the Toyota Electronic Parts Catalogue shows two knock sensors on the 4GR‑FSE (2.5L) and 2GR‑FSE (3.5L) V6 engines. On this V6, the sensors mount in the valley under the intake manifold, one per bank.

The knock sensor’s job is to “listen” for knock (pinging) and let the ECU trim ignition timing to protect the engine and keep it running sweet on Australian and New Zealand fuels. By detecting abnormal combustion early, it prevents detonation damage, reduces emissions, and helps maintain crisp throttle response. If the sensor or its wiring goes crook, the ECU often pulls timing as a safety net, so the car can feel doughy, thirstier, and may log a fault light.

As part of regular servicing, the knock sensor isn’t a routine replacement item, but a bit of care goes a long way. Under the bonnet, technicians should check the engine harness routing and connectors for heat-hardening, oil saturation, or brittle clips—especially after 10+ years and many kilometres. If fault codes P0325/P0330 appear, confirm with live data and a proper wiring check before swapping parts.

• Common signs of a knock sensor issue: reduced power, poor fuel economy, audible pinging under load, or a Check Engine lamp with the above DTCs.
• Recommended fuel: use the grade specified on the fuel flap/owner’s manual, many GR‑FSE engines expect premium petrol (95 RON or higher).

Replacement on a Mark X V6 usually requires removing the intake manifold. That means fresh manifold gaskets, careful cleaning of mating faces, and torqueing the new sensor(s) to specification with the correct orientation so the harness doesn’t chafe. Genuine Toyota or high-quality OEM (e.g., Denso) sensors are strongly preferred, cheap clones can mis-read knock and cause ongoing drivability grief.

After installation, clear codes, check for vacuum leaks, and perform an ECU readiness drive. Owners who hear persistent pinging should avoid heavy loads and get the vehicle scanned, left unchecked, real detonation can harm pistons, valves, or the catalyst. With a healthy knock sensor pair and the right fuel, the 2015 Mark X stays smooth, efficient, and happy over long Kiwi and Aussie kilometres.

Does the 2015 Toyota Mark X have a knock sensor?

Yes. The GRX130 V6 uses two knock sensors, one per bank. Toyota service information references DTCs P0325 and P0330 for those circuits, confirming their presence.

When should the knock sensor be replaced on a Mark X?

It’s only replaced when faulty—typically if DTCs are present and wiring checks out. Because access requires intake manifold removal, it’s smart to replace both sensors if one has failed and the vehicle has high kilometres.

Is it safe to drive with a bad knock sensor?

The ECU will usually retard timing to protect the engine, so it may feel sluggish and burn more fuel. Light driving may be possible, but it’s best to sort it promptly to avoid real knock and potential engine damage.