Parts for your 2009 Toyota Vitz|yaris-Camshaft sensor

2009 Toyota Vitz/Yaris Camshaft Sensor — Purpose, upkeep, and replacement tips

Yes, the 2009 Toyota Vitz/Yaris is fitted with a camshaft position sensor. This applies across its common XP90-series engines (1KR‑FE 1.0L, 2SZ‑FE 1.3L, and 1NZ‑FE 1.5L). Toyota’s technical literature confirms it: the Toyota Repair Manual for the 2005–2011 Yaris/Vitz lists DTCs such as P0340/P0343 for the Camshaft Position Sensor (CMP), the Toyota New Car Features documents describe the CMP signal being used for sequential fuel injection and VVT‑i control, and the Toyota Electrical Wiring Diagram shows the CMP circuit feeding the engine ECU. The Toyota parts catalogue for these engines also includes a dedicated CMP sensor mounted at the cylinder head.

On this model, the camshaft sensor keeps the engine management right on the money by telling the ECU exactly where the cam is in its rotation. That lets the ECU fire each injector at the right moment, time the ignition cleanly, and control VVT‑i for smooth torque and good fuel economy. Paired with the crank sensor, it also helps with misfire detection and reliable hot and cold starts. When the CMP plays up, owners may notice hard starting, rough idle, flat spots, poor fuel economy, the engine light on, and logged codes like P0340/P0343. In some cases the ECU can fall back to batch injection, but starting and drivability usually suffer.

There’s no scheduled replacement for the CMP sensor on a 2009 Vitz/Yaris, and it’s generally maintenance‑free. During routine servicing, it’s smart to visually check the sensor connector and harness where it runs across the top of the engine, make sure the clip is secure, and look for oil contamination from rocker cover weeps. Good, clean engine oil helps the VVT‑i system behave, which in turn keeps cam/crank correlation tidy. If a fault appears, confirm with scan data and basic checks first: inspect wiring continuity, verify the crank sensor is healthy, and rule out timing chain stretch or a jumped tooth if correlation codes are present.

Replacement is straightforward: disconnect the battery, pop off the engine cover, unplug the sensor at the cylinder head, remove the retaining bolt, swap the sensor (fit a new O‑ring and lightly oil it), reinstall, reconnect, clear codes, and check live data. No special relearn is typically needed on these Toyotas. Stick with a reputable brand or genuine part—cheap sensors can cause repeat faults. If in doubt, a technician can scope the cam/crank signals to confirm the fix.

• Typical symptoms: hard start, rough idle, hesitation, increased fuel use, MIL on (e.g., P0340/P0343)
• Service tip: inspect wiring and connector during every oil service
• If correlation codes persist, evaluate timing chain wear and VVT‑i operation

Popular questions

What are the signs of a failing camshaft sensor on a 2009 Vitz/Yaris?

Common tell‑tales are longer cranking, intermittent stalling, a lumpy idle, lack of power, and the engine light on with codes like P0340 or P0343. Fuel economy can drop, and cold starts may become hit‑and‑miss.

Because the ECU can sometimes run in a fallback mode, faults may be intermittent. A scan of live data and a wiring check usually narrows it down quickly.

Is it safe to keep driving with a dodgy camshaft sensor?

It will often run, but starting can be unreliable and drivability may be ordinary. Prolonged driving with faults can mask other issues (like timing chain stretch) and isn’t ideal for fuel economy.

Best bet: diagnose and repair promptly to avoid getting stranded and to keep the VVT‑i system performing properly.

How long does replacement take, and what else should be checked?

On these engines, swapping the sensor is usually a short job, often under an hour for a pro. While in there, check the connector pins, harness routing, and the rocker cover area for oil leaks that could contaminate the plug.

After replacement, clear the codes and confirm the cam/crank signals are clean. If correlation faults remain, assess the timing chain condition and VVT‑i oil control valve performance.