Parts for your 2008 Holden Commodore-Throttle position sensors

2008 Holden Commodore throttle-position-sensors (TPS)

Technical references confirm the 2008 Holden Commodore (VE series) is fitted with throttle-position-sensors. The Holden VE Commodore Service Manual – Engine Controls/Emissions (covering LY7/LE0 V6 and L98/L76 V8) and GM Service Information for Throttle Actuator Control describe an electronic (drive-by-wire) throttle body containing dual TPS circuits, plus an accelerator pedal position sensor. Diagnostic sections listing DTCs P0121–P0123, P0221–P0223 and P2135 further verify TPS monitoring and correlation checks. Parts catalogues for OE electronic throttle bodies for VE models also note the TPS is integral and non-adjustable. So, yes—this model uses throttle-position-sensors, and they’re built into the throttle body assembly.

The TPS on a 2008 Commodore tells the engine computer exactly how far the throttle blade is open. With that info, the car trims fuelling and spark, manages idle speed, smooths out gear changes, and coordinates traction and stability control. Because the VE runs a drive-by-wire setup, there are two independent TPS signals inside the throttle body for safety and accuracy, constantly cross-checked by the ECU.

As a service item, the TPS isn’t separately replaceable or adjustable—it’s part of the electronic throttle body. During regular servicing, it’s smart practice to check the throttle body connector and loom for corrosion or oil wicking, and use a scan tool to watch the throttle angle sweep smoothly from closed to wide open with no dropouts. If the throttle bore is dirty, a careful clean with a throttle-safe cleaner can help idle quality, don’t force the blade open by hand. After cleaning, perform a throttle/idle relearn with a capable scan tool (or follow the GM idle learn routine) so the ECU resets its targets.

When faults crop up, the dash may show “Engine Power Reduced,” the ESP/traction light may join in, and the car can go into limp mode. Common signs include a hunting idle, flat spots on tip-in, sudden surging, stalling when rolling to a stop, or harsh shifts. Typical TPS-related codes include:

• P0121, P0122, P0123 (TP sensor range/performance/low/high)
• P0221, P0222, P0223 (secondary TP faults)
• P2135 (TP sensor 1–2 correlation)

If those appear and wiring checks out, the fix is usually to replace the complete throttle body with an OE-quality unit, fit a new gasket/O-ring if required, and carry out the idle/throttle learn. It’s also worth verifying the accelerator pedal sensor data and grounds before pulling parts. As a guide, inspecting the throttle body and data every 30–40,000 kilometres keeps things sweet under the bonnet and reduces the odds of a surprise limp-home.

FAQs

Does a 2008 Holden Commodore have a throttle position sensor?
Yes. The VE Commodore uses an electronic throttle body with dual built-in throttle-position-sensors. There’s also an accelerator pedal position sensor, and the ECU cross-checks both systems for safety. The TPS isn’t a separate bolt-on part, it comes as part of the throttle body.

Where is the TPS on a 2008 VE Commodore?
It’s inside the electronic throttle body mounted on the intake plenum/throttle housing at the front of the engine. The dual TPS tracks the throttle blade angle. Don’t confuse it with the accelerator pedal sensor, which lives on the pedal assembly in the cabin.

How do you reset or relearn the TPS after cleaning or replacement?
The preferred method is using a scan tool to run the Idle Learn/Throttle Learn procedure. If a scan tool isn’t available, follow the GM idle learn routine (ignition and idle steps) and then drive the vehicle through mixed conditions. Ensure electrical connectors are sound, the battery is healthy, and accessories like A/C are off during the relearn.