Parts for your 2021 Lexus Is-Camshaft sensor

2021 Lexus IS camshaft sensor — what it does and when to service it

Short answer: yes, a camshaft sensor is fitted to the 2021 Lexus IS range. Technical sources that document this include the Lexus IS 2021 Repair Manual (engine control diagnostics for DTCs P0340/P0345/P0365, etc.), Lexus Electrical Wiring Diagram (EWD) for the IS platform, and the Lexus genuine parts catalogue listing camshaft position sensors for the 2.0‑litre turbo four and 3.5‑litre V6. These references show the ECM relies on camshaft position input for ignition timing, sequential injection, and variable valve timing control.

On a 2021 IS, the camshaft sensor tells the engine computer exactly where the cam(s) sit in their rotation. That little timing snapshot lets the car fire spark and inject fuel at the right moment and trim valve timing for smooth torque and better economy. If the signal goes missing or drifts, drivers can see a check‑engine light, hard starting, rough running, or codes like P0340/P0345 (V6 banks 1/2) and P0365/P0368 (four‑cylinder “B” sensor). The V6 typically uses two cam sensors (one per bank), while the turbo four commonly uses two on bank 1 (intake “A” and exhaust “B”).

There’s no fixed replacement interval for the camshaft sensor, it’s a non‑service item. That said, a quick check under the bonnet during routine servicing pays off. Inspect the connector and wiring for heat damage, broken clips, or oil intrusion, and make sure any rocker cover seepage is addressed so it doesn’t wick into the plug. Keeping to the correct engine oil grade and change schedule helps the variable valve timing system behave, which in turn keeps the sensor signal clean and predictable.

Chasing a fault? Before swapping parts, confirm with a scan tool and live data that the cam signal drops out or is implausible versus the crank signal. A wiggle test on the loom, a careful look for corrosion at the terminals, and a proper power/earth check can save guesswork. If replacement is needed, it’s a straightforward remove‑and‑refit with a single retaining fastener and an O‑ring, do it on a cool engine, lightly oil the new O‑ring, and refit to the factory torque. Sticking with a quality OEM‑spec sensor avoids intermittent gremlins, misfires, and repeat MILs down the track.

• Common symptoms: hard start when hot, uneven idle, flat spots, higher fuel use, MIL on.
• Relevant DTCs: P0340/P0341/P0345/P0346 (V6), P0365/P0368 (four‑cyl “B” sensor), among others.

Technical references consulted: Lexus IS 2021 Repair Manual (Engine/Hybrid System diagnostics for Camshaft Position Sensor G/G2), Lexus IS Electrical Wiring Diagram (engine control inputs), and Lexus Genuine Parts Catalogue for 2021 IS camshaft position sensors.

FAQs

How many camshaft sensors are in a 2021 Lexus IS?
It depends on the engine. The 3.5‑litre V6 uses two sensors, one for each bank. The 2.0‑litre turbo four generally has two on bank 1, monitoring intake (“A”) and exhaust (“B”) cams. If unsure, check the VIN/engine code or the parts catalogue to confirm your exact setup.

What fault codes point to a bad camshaft sensor on a 2021 IS?
Common codes include P0340/P0341 (Bank 1), P0345/P0346 (Bank 2) on the V6, and P0365/P0368 for the “B” sensor on the four‑cylinder. These may be accompanied by rough running, extended cranking, or limp behaviour. Always verify wiring, power and earth before replacing the sensor.

Can a camshaft sensor be cleaned, or does it need replacing?
If the connector is oily or dirty, a careful clean can help signal integrity, but a failed sensor itself is usually replaced rather than cleaned. Use the correct oil, fix any cover leaks, and keep connectors sound to maximise service life.