Parts for your 2020 Holden Commodore-Knock sensor

2020 Holden Commodore knock sensor — purpose, care and replacement tips

Yes, the 2020 Holden Commodore (ZB) uses knock sensors. Technical sources including GM Service Information for the ZB Commodore (listing DTCs P0324–P0334 for knock-sensor faults), the Opel Insignia B workshop manual (the ZB’s platform mate), and ACDelco’s parts catalogue for 2018–2020 Commodore confirm block-mounted knock sensors across the 2.0‑litre turbo petrol and 3.6‑litre V6, with diesel variants using a combustion noise/knock sensor as part of combustion control.

The knock sensor’s job is to “listen” for detonation (pinging) and let the engine computer trim ignition timing and, on turbo models, boost, to protect the donk and keep performance crisp. It’s a small piezo sensor bolted to the block that translates vibration into a signal the ECU can interpret. On the 2.0T it’s typically mounted on the block beneath the intake side, on the LGX 3.6 V6 there are usually two sensors in the valley under the manifold.

It’s not a routine service item, but it’s absolutely critical. A crook or unplugged knock sensor can trigger a check engine light, drop power as the ECU plays it safe, and push fuel use up. If you’re chasing rattly “ping” under load, random timing pull, or codes like P0325–P0334, don’t ignore it.

• Common signs it needs attention: pinging on hills, poor acceleration, higher fuel use, MIL on with knock-sensor codes.
• Good habits: run the recommended 95/98 RON for petrol variants, keep cooling and intake systems healthy, and check for wiring rub-through during scheduled servicing.

Replacement is straightforward for a pro and a bit fiddly for DIY. Disconnect the battery, remove what’s in the way (often the intake manifold on V6s), and access the sensor. The mounting face on the block must be clean and dry—no sealants. Fit an OE-quality sensor, route the loom away from heat and sharp edges, and torque the bolt to spec (around 20 N·m is common on GM units, but always follow the exact spec in the service info for your engine code). Clear codes and perform any required ECU learn procedure.

Because the sensor is essentially the engine’s ears, avoiding false noise is key. Keep engine mounts, exhaust brackets and under‑bonnet hardware tight so the ECU isn’t chasing phantom knock. With the right fuel, healthy cooling and a sensor that’s talking properly, the ZB Commodore delivers the smooth, strong pull it’s known for—all while protecting itself on Aussie and Kiwi roads.

• Does the 2020 Holden Commodore have a knock sensor?
  Yes. Both the 2.0T petrol and 3.6 V6 use block-mounted knock sensors (typically two on most variants), and diesel versions use a combustion noise/knock sensor for precise combustion control.
• Where is the knock sensor located?
  On the 2.0T it’s usually on the side of the block below the intake. On the 3.6 V6, the pair sit in the valley under the intake manifold. Access often requires removing intake hardware.
• What fault codes point to a knock-sensor issue?
  Expect codes in the P0324–P0334 range. You might also see timing pull in data logs, reduced power, or pinging. Always diagnose wiring and grounds before condemning the sensor.