Parts for your 2014 Lexus Is-Knock sensor

2014 Lexus IS knock sensor: what it does and when to replace it

Based on technical references including the Lexus IS Repair Manual for the GSE30/35/AVE30 series (2013–2017), the Lexus Electronic Parts Catalogue, and the Lexus/Toyota Electrical Wiring Diagram (EWD), the 2014 Lexus IS does use a knock sensor. The V6 petrol models (IS 250 4GR‑FSE and IS 350 2GR‑FSE) are equipped with two knock sensors mounted in the V of the engine beneath the intake, while the IS 300h (2AR‑FSE) uses a knock sensor on the block. These factory sources describe the “Knock Control” strategy within the Engine Control section and list the sensor(s) as serviceable components.

On the 2014 Lexus IS, the knock sensor listens for the high-frequency vibration caused by detonation (knock) and lets the engine control module trim ignition timing to protect the motor and keep things smooth. It’s a quiet achiever: better efficiency, safer combustion under load, and happier long-term engine health—especially important with Aussie and Kiwi summer temps, steep climbs, and the occasional tank of average fuel.

There’s no scheduled replacement for the knock sensor—it's a fit-and-forget item unless there’s a fault. Telltale signs include a check engine light with codes like P0325–P0334, rattly-sounding acceleration (pinging), flat performance, or unusually high fuel use. Before throwing parts at it, a good workshop will check fuel quality, engine earths, wiring integrity, and the connector, then confirm live data and DTCs with a scan tool.

If replacement is needed, access differs by engine. On the V6 IS 250/350, the sensors sit under the intake manifold in the valley, the intake and related plumbing usually need to come off. On the IS 300h four-cylinder, it’s mounted on the block below the intake side. Using a genuine or high-quality equivalent sensor and torquing it exactly to the workshop manual spec is critical—over- or under-tightening can skew readings. Keep the mating surface clean and dry, route the harness exactly as per the manual, and clear codes after the job. A short drive cycle or idle learn may be required so the ECU can recalibrate knock control.

As part of regular servicing, it’s smart to keep an eye on any stored DTCs, use the recommended octane, and check for intake or exhaust leaks that can mimic knock. That way, the sensor can do its job and the IS stays sharp, efficient, and ready for the next open road.

Popular questions about the 2014 Lexus IS knock sensor

Where is the knock sensor on a 2014 Lexus IS?
On IS 250/350 V6 models, there are two sensors tucked in the V under the intake manifold. On the IS 300h, the sensor is bolted to the block on the intake side. Access on the V6 usually requires removing the upper intake gear, the hybrid is typically simpler to reach.

Can you drive with a faulty knock sensor?
It’ll usually run, but it’s not ideal. The ECU may pull timing to protect the engine, which means sluggish performance and higher fuel use. If there’s actual knock that the ECU can’t manage properly, long-term engine damage is possible. Best bet: scan it, fix the cause, and get back to normal.

How much does replacement cost in AU/NZ?
Parts generally run about $150–$350 AUD/NZD per sensor depending on brand. Labour varies with engine: expect roughly 2–4 hours for the V6 due to intake removal, and around 1–2 hours for the 2.5-litre hybrid. A proper diagnosis first can save time and coin.