Parts for your 2009 Mitsubishi Lancer-Throttle position sensors

2009 Mitsubishi Lancer throttle position sensor — what’s fitted and what it does

Yes, the 2009 Mitsubishi Lancer uses throttle position sensors, but not as a separate, bolt-on part like older cable-throttle cars. It runs electronic throttle control (drive‑by‑wire), where dual throttle position sensors are built into the throttle body. This setup is documented in the Mitsubishi Lancer CJ/CF workshop manual (Group 13A – Engine Electrical, Electronic Throttle Control), which shows two TP sensor tracks inside the throttle body, and in the Mitsubishi electronic parts catalogue where the sensor is not listed separately from the throttle body assembly.

On a 2009 Lancer, the throttle position sensors constantly report the throttle plate angle to the engine control module. They work in pairs for redundancy, helping the ECU manage idle speed, acceleration, emissions and cruise control with smooth, accurate inputs. If the readings don’t agree, the car can drop into limp mode to protect the engine and driver.

Servicing-wise, it’s a tidy bit of kit. Because the TPS is integrated, most fixes come down to cleaning, relearning, or replacing the throttle body as a unit. A workshop will typically:

• Scan for fault codes like P0120–P0124, P0220–P0223 or P2135 and check live data for TP Sensor A/B agreement.
• Clean the throttle bore and plate using throttle‑safe cleaner (don’t force the plate by hand).
• Perform a throttle/idle relearn with a scan tool after cleaning, battery disconnection or throttle body replacement.

Symptoms of trouble can include erratic idle, hesitation, surging cruise control, a check engine light, poor fuel economy and the occasional limp-home event. If cleaning and relearn don’t sort it, replacement of the throttle body is the go. On the 4B11/4B12 engines, that means a new gasket, correct torque on the mounting bolts, and a proper adaptation/relearn. Many independent workshops in Australia and New Zealand will also check the accelerator pedal position sensor at the same time, as the ECU validates both signals together.

There’s no set replacement interval — it’s more about condition and kilometres. As part of regular servicing, aim to inspect and clean the throttle body every 40,000–60,000 km, especially if most driving is around town. Keep the battery and charging system healthy too, low voltage can upset electronic throttle systems and trigger false TPS codes. With a clean bore, good electrical connectors and a proper relearn, the Lancer’s throttle sensors will generally play nice for years.

Popular questions

Where is the throttle position sensor on a 2009 Lancer?
It’s inside the electronic throttle body on the intake manifold. There are two sensor tracks built in, so you won’t find a separate external TPS to swap. If it fails, the fix is usually a throttle body assembly.

Can the TPS be replaced on its own?
Not on most 2009 Lancer models. Mitsubishi supplies the throttle body with the TPS and actuator as one unit. Technicians will clean and relearn first, if readings are still out, they’ll replace the assembly and complete an adaptation procedure.

Do I need a relearn after cleaning or replacing the throttle body?
Yes. A throttle/idle relearn lets the ECU recalibrate the plate position. Workshops use a scan tool to run the procedure. Without it, you can get unstable idle or delayed throttle response after servicing.