Parts for your 2011 Toyota Mark x-Throttle position sensors

2011 Toyota Mark X Throttle Position Sensor (TPS)

Yes, the 2011 Toyota Mark X uses a throttle position sensor. Toyota’s own technical material for the GRX130/133 series describes Electronic Throttle Control (ETCS-i) with a “Throttle with Motor Body Assembly” that integrates dual throttle position circuits (often referred to as VTA1/VTA2) and a throttle control motor. The related diagnostic trouble codes (e.g., P0120–P0124 and P0220–P0223 for throttle/pedal position circuits) are listed in Toyota workshop literature for the 4GR‑FSE and 2GR‑FSE engines, confirming the presence of a TPS within the throttle body. Toyota’s parts catalog also notes the throttle body assembly includes the position sensor from factory.

The TPS on a Mark X tells the engine control module exactly how far the throttle blade is open, so it can match air, fuel and ignition, manage idle speed, smooth out gear changes, and keep emissions tidy. Because it’s drive-by-wire, the car also uses an accelerator pedal sensor, the ECM compares that with the TPS for accuracy. If those don’t agree, it’ll throw a code and may drop into limp mode to protect the engine and gearbox.

There’s no routine replacement interval for the TPS on this model because it’s built into the throttle body. During regular servicing, the smart play is to keep the air path clean: a careful throttle bore clean with the right cleaner helps, but don’t flood the sensor area and don’t force the blade by hand. Check the connector for corrosion, broken locks, or chafed wiring under the bonnet—heat and vibration can be unkind over the kilometres.

Diagnosis is best done with a scan tool: look for smooth throttle angle change, healthy correlation between the two TPS signals, and no sudden dropouts. If the sensor is faulty, the fix is typically a complete throttle body replacement. Use a new gasket, torque fasteners to spec from the Toyota manual, and ensure battery voltage is stable during the job. After refit, perform the throttle/idle learn procedure (or use a capable scan tool) so the ECM knows the new zero and full-open positions. Clear any codes, check for vacuum leaks, then road test to confirm clean idle, crisp tip-in and normal shifting. Quality OE or reputable aftermarket throttle bodies matched to your VIN are the safest bet for long-term reliability.

• Common signs: erratic idle, stalling at lights, sluggish response, sudden limp mode, high fuel use, and TPS/ETCS DTCs.
• Longevity tips: keep filters fresh, avoid water ingress at connectors, and don’t spray harsh solvents into the throttle body.

Does the 2011 Mark X actually have a throttle position sensor?

It does. Toyota’s ETCS‑i system on the GRX130/133 Mark X uses a throttle body with an integrated TPS (two position circuits). The presence of TPS-related DTCs in Toyota service documentation backs this up.

Can the TPS be replaced on its own, or does the whole throttle body need doing?

On this model it’s generally part of the throttle body assembly and not serviced separately. If the sensor fails, the usual repair is to replace the complete throttle with motor body assembly, then carry out the throttle learn.

What symptoms point to a failing TPS on a Mark X?

Think rough or hunting idle, hesitation, sudden loss of power with limp mode, poor fuel economy, and warning lights. Scan results showing TPS correlation faults or codes like P0121/P0221 are a giveaway.