Parts for your 2007 Toyota Prius-Throttle position sensors

2007 Toyota Prius throttle position sensor (TPS): what it does and when to service it

Yes, the 2007 Toyota Prius uses a throttle position sensor. In this model, the TPS isn’t a separate bolt-on part, it’s built into the electronic throttle body as part of Toyota’s ETCS‑i (Electronic Throttle Control System – intelligent). Toyota’s New Car Features for the 2004–2009 Prius (XW20, 1NZ‑FXE) describes the throttle body containing a throttle control motor and dual TPS circuits (often called VTA1/VTA2) for redundancy. The Toyota Repair Manual for the same generation details ETCS‑i operation and the diagnostic trouble codes that monitor the TPS circuits (e.g., P0120–P0123 and P2135). Toyota’s parts catalogue for the 2007 Prius also lists the throttle body assembly as including the built‑in sensors, rather than a standalone TPS.

On a 2007 Prius, the TPS tells the engine control module the exact angle of the throttle plate. Because the car is drive‑by‑wire, the ECU commands a small electric motor to position the plate, and the TPS sends back precise feedback so it can match airflow to driver demand. That tight loop is crucial for smooth take‑offs, clean gearless acceleration, stable idle control when the engine cycles on and off, and reliable “limp‑home” behaviour if a fault crops up.

There’s no scheduled TPS replacement interval on this Prius, and because the sensor is integrated, any TPS fault typically means replacing the whole throttle body. Before getting the spanners out, a good workshop will scan live data for VTA1/VTA2 to check for smooth, matching voltage sweeps, wiggle‑test the harness at the throttle body under the bonnet, and look for fault codes like P0120–P0123 or P2135. If readings are clean and codes point elsewhere, the culprit may be the accelerator pedal position (APP) sensor instead, which is a separate unit at the pedal.

As part of routine servicing, it’s smart to clean the throttle bore every 80–100,000 kilometres, especially if there’s sticky residue that can make the plate hang. Use throttle‑body‑safe cleaner, don’t manually force the plate wide open, and fit a fresh gasket if the body is removed. If the throttle body is replaced due to a TPS fault, disconnect the 12‑volt battery before starting, then perform an ETCS/Throttle reset with a scan tool (Techstream “Reset Memory/ETCS Initialization”) so the ECU relearns its baseline. Typical symptoms of a crook TPS on this Prius include erratic idle when the engine is running, flat spots, reduced power, cruise control drop‑outs, and the MIL on with the codes noted above. When in doubt, graph the signals—good sensors give a smooth, linear trace without dropouts.

• Signs it needs attention: MIL on with P0120–P0123/P2135, surging or hesitation, poor throttle response, limp mode.
• Quick care tip: keep the throttle plate and bore clean, inspect the connector for moisture or corrosion.
• Replacement note: TPS is part of the throttle body assembly—replace as a unit and initialise ETCS afterwards.

Popular questions

Does a 2007 Prius actually have a throttle position sensor?
It does. The Prius runs a drive‑by‑wire setup where the TPS is integrated into the throttle body and provides dual feedback signals (VTA1/VTA2) to the ECU. Toyota’s service literature for the 2004–2009 model spells this out and even defines TPS‑related DTCs that the ECU can set.

Can the TPS be replaced on its own in a 2007 Prius?
Not as a separate service part. Toyota supplies the throttle body as a complete assembly with the TPS and throttle motor built in. If the TPS fails testing, the fix is to replace the throttle body, then run an ETCS reset so the ECU relearns positions.

Do you need to calibrate anything after replacing the throttle body?
Yes—perform an ETCS/Throttle reset with a suitable scan tool (e.g., Techstream). This clears learned values so the ECU can relearn the closed and operating positions. Skipping this step can leave you with a rough idle, lazy response, or stored fault codes.