Parts for your 2016 Holden Astra-Throttle position sensors

2016 Holden Astra throttle-position sensor: what it is and how it’s handled

Based on GM Service Information (SI) for the Astra K/BK (MY16) Electronic Throttle Control chapter, and the Holden/ACDelco parts catalogue for 2016 Astra models, the vehicle uses an electronic throttle body with an integrated throttle-position sensor (TPS). It’s not a separate, stand‑alone sensor you can buy on its own. The accelerator pedal also carries a dual-track pedal position sensor, while the throttle body houses a dual-track TPS for feedback to the engine control module. Typical GM DTCs tied to this setup include P0121–P0123 and P2135. So yes—the TPS function is present on the 2016 Holden Astra, but it’s built into the throttle body assembly.

On the 2016 Astra, the throttle-position sensor tells the ECU exactly where the throttle plate sits, so fuelling and spark timing line up with the driver’s right foot. Because it’s a drive‑by‑wire system, that little feedback loop is crucial for smooth take-offs, clean gear changes and keeping emissions in check. When the TPS signal goes flaky, the Astra can drop into limp mode, idle rough, surge on light throttle or light the check-engine lamp.

Unlike old-school setups, the TPS in this Astra isn’t a separate bolt-on. If the sensor fails or the signal doesn’t agree with the accelerator pedal sensor, the usual repair is to replace the complete throttle body. That sounds bigger than it is—access is decent, and with the right scan tool a throttle relearn is straightforward.

• Tell-tale signs: hesitant acceleration, unstable idle, poor fuel economy, throttle lag, or codes like P0121/P0122/P0123/P2135.
• First checks: battery health and grounds, throttle-body connector pins, and wiring chafes near the intake and battery tray.
• Cleaning: a light clean of the throttle bore and plate with throttle-safe cleaner can sort sticky behaviour caused by carbon. Don’t force the plate by hand.
• Relearn: after cleaning or replacement, perform an electronic throttle/idle relearn—ideally with a scan tool. This helps the ECU re-map the plate position.

If replacement’s on the cards, go for quality OE or reputable aftermarket units. New gasket or seal is recommended, and clear any DTCs after the relearn. With regular servicing—clean air filter, sound battery voltage, and the occasional throttle-body clean—the Astra’s electronic throttle and its integrated TPS usually rack up plenty of kilometres without drama.

FAQs

Can the TPS be replaced separately on a 2016 Holden Astra?
No. On the BK/K Astra the TPS is integrated into the electronic throttle body and isn’t serviced as a separate part. If testing confirms a TPS fault, the fix is to replace the whole throttle body assembly and carry out a throttle relearn.

What symptoms point to a dodgy TPS on a 2016 Astra?
Common signs include erratic idle, surging or hesitation on light throttle, poor fuel economy, and the car dropping into limp mode. Scan tools often show codes like P0121–P0123 or P2135 indicating a mismatch between pedal and throttle signals.

Do I need a relearn after cleaning or replacing the throttle body?
Yes, a throttle/idle relearn is recommended after any throttle-body work. A proper scan-tool routine is best. Without it, the ECU may struggle to track the plate position, leading to high idle, stalling, or delayed throttle response.