Parts for your 2010 Toyota Mark x-Crank angle sensor

2010 Toyota Mark X Crank-Angle Sensor: Purpose, Care and Replacement

Yes, the 2010 Toyota Mark X is fitted with a crank-angle sensor (Toyota calls it the crankshaft position sensor). Technical references that confirm this include the Toyota GRX130 Mark X Repair Manual and Toyota’s Electronic Parts Catalogue for the 4GR-FSE (2.5L) and 2GR-FSE (3.5L) engines, both of which list and test procedures for the crankshaft position sensor as part of the engine control system.

On this V6, the sensor reads a toothed wheel on the crank to tell the ECU exactly where the pistons are and how fast they’re spinning. That data is critical for spark timing, fuel injection, and VVT-i control. If it goes out of whack, the ECU can’t time things properly, so starting, drivability and emissions all suffer.

There’s no scheduled replacement for the crank-angle sensor on a Mark X, but it’s worth a quick check at regular services. Look for oil seepage at the sensor O-ring, damaged wiring, loose connectors, or metal debris sticking to the sensor tip. Keep the area clean—don’t blast it with a pressure washer. On the GRX130’s longitudinal layout, the sensor is mounted low on the engine block facing the crank reluctor, it’s typically accessed from underneath. The GR V6 uses one crank sensor and separate cam sensors on each bank.

• Common symptoms of a dodgy crank-angle sensor: long crank or no-start when hot, intermittent stalling, rough idle, sudden tach drop, and engine codes like P0335/P0339.
• If you’re replacing it: use a quality Toyota/Denso sensor that matches your engine (4GR-FSE or 2GR-FSE).
• Basic steps: disconnect the battery negative, raise and support the front, unplug the connector, remove the retaining bolt, and ease the sensor out.
• Lightly oil the new O-ring, seat the sensor, and torque the bolt to about 9 N·m. Reconnect, clear codes, and take a short drive so the ECU can stabilise idle and trims.
• If issues persist after replacement, check the harness, grounds, and the crank trigger wheel for damage or excessive end-float.

Done right, the sensor is a straightforward swap and restores crisp starting and smooth running, just as Toyota intended.

Popular questions about the 2010 Toyota Mark X crank-angle sensor

Where is the crank-angle sensor located on a 2010 Toyota Mark X?
On the GRX130 Mark X, it’s mounted low on the engine block facing the crankshaft reluctor wheel. With the car on stands, it’s typically accessed from underneath near the front of the engine. Expect one crank sensor and two separate cam sensors (one per bank).

Do I need to program the ECU after replacing the crank-angle sensor?
No special programming is usually needed. After fitting, clear any fault codes, then let the engine warm up and take a short drive so the ECU can relearn idle and fuel trims. If codes return, inspect wiring and the trigger wheel.

What are the tell-tale signs the sensor is failing?
Hard starting (especially hot), random stalling, rough idle, a dead tach during crank, and OBD-II codes like P0335/P0339 are the big giveaways. If those show up, test the sensor per the Toyota Repair Manual before replacing.