Parts for your 2006 Toyota Prius-Camshaft sensor

2006 Toyota Prius Camshaft Sensor

The 2006 Toyota Prius (NHW20, 1NZ‑FXE engine) is fitted with a camshaft position sensor. Toyota’s Repair Manual for 2004–2009 Prius and the Electrical Wiring Diagram list the Camshaft Position Sensor (often labelled G2) and related diagnostic trouble codes P0340 and P0341, confirming this component is absolutely relevant on this model.

On a Gen 2 Prius, the camshaft position sensor works with the crankshaft sensor to tell the engine control module exactly which stroke each cylinder is on. That info is vital for quick, clean starts when the hybrid system spins the engine, for accurate fuel injection and ignition timing, and for managing VVT‑i on the intake cam. Without a crisp cam signal, the car can struggle to start the petrol engine, run a bit rough once it does, or drop into a reduced‑performance mode, and it will usually light the MIL with codes like P0340/P0341.

It’s a solid‑state, Hall‑effect style sensor mounted on the cylinder head at the timing chain end. There’s no scheduled replacement interval, it’s largely a fit‑and‑forget item. As part of servicing, smart owners and techs do a quick visual: check the connector for corrosion or damage, ensure the harness isn’t chafed, and look for oil weeping around the sensor’s O‑ring or the nearby rocker/valve cover. Keeping oil changes on time helps, because sludgy oil can affect VVT‑i behaviour and muddy faultfinding when cam timing performance codes appear.

If replacement is needed, it’s a straightforward job. Make sure the car is fully off (not in READY) and disconnect the 12‑volt negative terminal to prevent the hybrid system from waking the engine. Unplug the sensor, remove the retaining bolt, and pull the sensor straight out. Lightly oil the new O‑ring, seat the new sensor, refit the bolt (tightened to the factory spec), reconnect the plug, and restore the 12‑volt supply. Clear any stored codes and perform a couple of drive cycles to confirm all’s sweet. Using a quality OEM‑equivalent sensor is recommended, as signal quality matters for smooth hybrid starts.

• Common symptoms when faulty: intermittent no‑start of the engine, rough running when the engine kicks in, poor fuel economy, MIL on with P0340/P0341.
• Handy tip: rule out wiring and oil contamination before condemning the sensor.

Does a 2006 Prius actually have a camshaft sensor?

Yes. Toyota’s 2004–2009 Prius service documentation identifies a Camshaft Position Sensor (G2) on the 1NZ‑FXE engine, and the ECM sets cam‑sensor‑related DTCs such as P0340 and P0341 if there’s a fault. It lives on the cylinder head near the timing chain end.

What are the tell‑tale signs it’s failing?

Owners may notice the petrol engine takes longer to fire when the hybrid system tries to start it, a rough idle once it does, or the car feeling a bit flat. The check‑engine light often appears, commonly logging P0340 or P0341. Because the Prius starts and stops the engine frequently, the symptoms can seem intermittent.

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

The car may still run, but performance and fuel use can suffer, and it can occasionally fail to start the engine when needed. That’s not ideal for reliability on longer trips. It’s best to diagnose promptly and replace the sensor or repair the wiring before it strands the driver.