To adjust the throttle position sensor on your Opel Corsa C 2006, follow these steps:

1. Locate the throttle position sensor. It is usually located on the throttle body.

2. Loosen the sensor's mounting bolts.

3. Connect a voltmeter to the sensor's signal wire. The signal wire is usually the one in the middle.

4. Turn the ignition on but do not start the engine.

5. Slowly depress the gas pedal until the throttle is fully open.

6. Observe the voltmeter. It should read between 0.5 and 1.0 volts.

7. If the voltage is outside this range, adjust the sensor's position by rotating it slightly.

8. Retest the voltage and adjust as needed until the voltage falls within the proper range.

9. Tighten the mounting bolts and retest to ensure the voltage remains within range.

10. Start the engine and confirm that the idle is smooth with no hesitation or surging.