Parts for your 2022 Subaru Impreza-Throttle position sensors

2022 Subaru Impreza throttle position sensors: what they do and how to look after them

Technical sources confirm throttle position sensors are absolutely used on the 2022 Subaru Impreza. The model runs electronic throttle control on the FB20 engine, with dual throttle position sensors integrated into the throttle body. Subaru service literature for 2017–2022 Impreza (Engine/Diagnostics, FB20) describes these as non‑adjustable sensors built into the electronic throttle module, with diagnostic routines covering DTCs P0121/P0122/P0123 (TPS “A”), P0221/P0222/P0223 (TPS “B”), and P2135 (A/B correlation). Subaru’s Tech Info guidance indicates replacement of the throttle body assembly if the sensor tracks are faulty, followed by an idle/ETC relearn. This layout is typical of Bosch-style electronic throttle systems used by Subaru during these years.

On this Impreza, the throttle position sensors tell the engine computer exactly how far the throttle plate is open. That data is blended with accelerator pedal position, air flow, and engine load to get smooth throttle response, stable idle, decent fuel economy, and proper emissions. Because they’re built into the throttle body, there’s nothing to “tune” or adjust—when they’re healthy, they just work in the background every time the driver taps the pedal.

As part of regular servicing, there are a few smart habits that help the throttle body and its sensors live a long life:

• Keep the intake tract clean and the air filter replaced on time to reduce oily deposits that can foul the throttle plate and skew sensor feedback.
• If cleaning the throttle body, avoid soaking the electronics. Use throttle-safe cleaner sparingly, wipe the bore and blade, and don’t force the plate open. After cleaning, perform an idle learn/ETC reset with a scan tool so the ECU relearns minimum airflow.
• Inspect the throttle body electrical connector under the bonnet for corrosion or damaged pins. A poor connection can throw TPS correlation codes and limp-home behaviour.

Symptoms of a crook TPS on a 2022 Impreza can include an illuminated check engine light, uneven idle, hesitation, poor shift quality in autos, cruise control dropping out, or the car going into reduced power mode. If any of the above shows up, a scan of live data (throttle angle vs pedal angle) and stored codes will usually point the way.

When replacement is needed, the fix is the complete throttle body assembly. It’s a straightforward job—battery disconnected, intake duct off, coolant hoses (if fitted) and connector removed, then swap the unit and torque the bolts to spec. Finish with an idle/ETC relearn and a road test to confirm smooth operation. There’s no set replacement interval, it’s condition-based. With clean air and the right servicing, they generally last for many kilometres across Aussie and Kiwi roads.

• Common TPS-related DTCs on this model: P0121–P0123, P0221–P0223, P2135.
• Technical references: Subaru Impreza 2017–2022 Service Manual (Engine/Diagnostics, FB20), Subaru Tech Info (ETC/Throttle Body), and standard OBD-II diagnostic routines for ETC systems.

Popular questions about 2022 Subaru Impreza throttle position sensors

Does the 2022 Subaru Impreza have a separate throttle position sensor I can replace?
It doesn’t. The throttle position sensors are integrated into the electronic throttle body as dual tracks. If a sensor circuit fails, Subaru service information calls for replacing the throttle body assembly and then performing an idle/ETC relearn with a scan tool.

What are the signs the TPS is failing on a 2022 Impreza?
Drivers may notice a check engine light, sluggish response, rough or hunting idle, cruise control cancelling, or the vehicle dropping into limp mode. Scan for DTCs such as P0121–P0123, P0221–P0223, or P2135 and compare live throttle angle to pedal angle to confirm.

Should the TPS be cleaned or adjusted during servicing?
There’s no adjustment on this model. During a service, a careful throttle body clean can help if deposits are building up, but avoid soaking the electronics. After cleaning, run an idle/ETC relearn so the ECU resets its throttle targets.