Parts for your 2010 Toyota Mark x-Camshaft sensor

2010 Toyota Mark X Camshaft Sensor: Purpose and Servicing

Based on technical sources, the 2010 Toyota Mark X (GRX130 series) is fitted with camshaft position sensors. Toyota’s Repair Manual for the 4GR‑FSE and 2GR‑FSE engines identifies the “Camshaft Position Sensor (G signal)” as part of the engine control system and lists related DTCs such as P0340/P0341 (Bank 1) and P0345/P0346 (Bank 2). The Toyota Electrical Wiring Diagram (EWD) for GRX13# shows dedicated CMP sensor circuits on both cylinder banks, and the Toyota Electronic Parts Catalogue (EPC) lists camshaft position sensor components for these engines.

On the 2010 Toyota Mark X, the camshaft sensor plays a key role in how smoothly the V6 runs. It tracks the exact position of the camshaft(s) so the ECU can time fuel injection and spark correctly, and keep Dual VVT‑i phasing right on the money. With direct injection on the 4GR‑FSE and 2GR‑FSE, accurate cam timing helps cold starts, emissions, and overall power delivery. This model typically has two camshaft sensors, one per bank, mounted near the front of the cylinder heads.

It’s not a regular replacement item, but it does deserve attention during servicing. A tech will usually:

• Visually check the sensor bodies, connectors, and wiring looms under the bonnet for oil wicking, heat damage, or brittle clips.
• Scan for fault codes like P0340/P0341/P0345/P0346 and look at live data for cam/crank synchronisation and VVT target vs actual.
• Confirm with an oscilloscope if needed, as that quickly shows a lazy or noisy signal.

Common symptoms of a failing cam sensor include hard starting (especially hot), rough idle, hesitation, poor fuel economy, and the MIL lighting up. If left too long, it can trigger limp behaviour and misfires. Replacement is straightforward: disconnect the battery, pull the engine cover, unplug the sensor, remove the retaining bolt, twist the sensor out, lightly oil the new O‑ring, fit the new unit, and tighten to the factory spec. After that, clear codes and road test, no fancy relearn is usually required, as the ECU adapts.

Good practice in Aus/NZ is to use genuine or reputable aftermarket sensors, keep the connectors clean, and make sure any engine oil leaks are sorted so they don’t contaminate the sensor. While at it, check the crankshaft sensor wiring too—these two signals work as a pair, and tidy wiring avoids intermittent gremlins. With the right part and a careful install, the Mark X will start crisply and pull cleanly right across the revs.

Popular questions about the 2010 Toyota Mark X camshaft sensor

How many camshaft sensors does a 2010 Mark X have?
Most 2010 Mark X V6s (4GR‑FSE and 2GR‑FSE) use two camshaft sensors—one per bank—so the ECU can track cam position on both sides. Always confirm by VIN or checking the service manual for the exact engine variant.

Can it be driven with a faulty camshaft sensor?
It might run, but it can be rough, hard to start, and may stall. Fuel economy suffers, and it can drop into a protective mode. It’s best to fix it promptly to avoid being stranded and to protect the catalytic converters from misfire damage.

What fault codes point to a camshaft sensor issue?
Typical codes include P0340/P0341 (Bank 1) and P0345/P0346 (Bank 2). These indicate circuit or performance faults for the camshaft position sensor. A proper diagnosis should still check wiring, connectors, and VVT operation before replacing parts.