Parts for your 2019 Audi Q5-Knock sensor

2019 Audi Q5 knock sensor — what it does and when to sort it

Yes, the 2019 Audi Q5 petrol models are fitted with knock sensors. Audi’s factory repair information (ElsaWin/erWin for FY-series Q5, 2017–2020), the Audi ETKA/PartsLink24 parts catalogue, and widely used diagnostic references (e.g., Ross‑Tech VCDS label files and OBD‑II DTC lists showing P0325/P0327/P0328 for the FY Q5 engines) all confirm knock sensors on the 2.0 TFSI (EA888) and the SQ5’s 3.0 TFSI (EA839). Diesel variants typically don’t use a traditional knock sensor in this platform, so the part’s relevance is for petrol Q5s.

On the 2019 Q5 petrol engines, the knock sensor is a small piezoelectric microphone bolted to the engine block. It listens for high‑frequency vibration that indicates detonation (also called “knock”). When the ECU hears knock, it trims ignition timing and fuelling on the fly to protect the engine and keep power smooth. That’s why a healthy knock sensor helps with efficiency, drivability and engine longevity, especially on our variable‑quality fuels across Australia and New Zealand.

As a servicing item, the knock sensor is “fit and forget” — it isn’t replaced on a schedule. However, it should be checked if you’re chasing symptoms like rattly pinging under load, a Check Engine Light with codes such as P0325/P0327/P0328, sluggish performance, poor fuel economy, or sudden reduced power. Visual checks during routine servicing are simple: look for oil contamination on the sensor or harness, chafed wiring, broken clips, or signs it’s been disturbed during other work.

If replacement is needed, it’s a straightforward but precision job. The sensor must be mounted clean and dry to the block, in the correct orientation, and tightened exactly to the factory torque. Over‑ or under‑torque can skew its readings and cause false knock events or missed detection. Always use the correct part number for your engine code (EA888 four‑cylinder uses two sensors, the EA839 V6 in the SQ5 has one per bank), and follow the Audi workshop procedure for bolt reuse/replacement and routing the loom away from heat and sharp edges.

After fitting, clear fault codes and perform a road test with a proper scan tool to confirm knock control is behaving normally. Given the sensor’s role as engine insurance, many owners choose an OEM sensor and have an experienced Audi/VAG technician handle the torque‑critical install.

• Does the 2019 Audi Q5 have a knock sensor?

  Yes — on petrol models (2.0 TFSI and SQ5 3.0 TFSI). Audi service documentation and parts catalogues list block‑mounted knock sensors for these engines. Diesel variants in this year typically don’t use a conventional knock sensor.

• What are common signs of a failing knock sensor on a 2019 Q5?

  Check Engine Light with P0325/P0327/P0328, metallic “ping” under load, flat spots, poor economy, or timing being pulled in logs. Wiring damage or oil‑soaked connectors can trigger the same symptoms.

• Should the knock sensor be replaced during routine servicing?

  No. It’s not a scheduled replacement item. Replace only if diagnosed faulty or damaged, and ensure correct torque and orientation during installation.