What happened when the Audi A4L tail gas purification indicator light came on?

Audi A4L tail gas purification indicator lights up. This situation shows that the Audi A4L idle motor needs cleaning. After cleaning the Audi A4L idle motor, this problem can be eliminated. The specific operation steps of cleaning Audi A4L idle motor are as follows:

First find the Audi A4L idle motor.

Second, unplug the Audi A4L idle motor.

Third, unscrew the screws that fix the Audi A4L idle motor.

4. Dismantle the idle motor of Audi A4L as a whole and prepare for cleaning.

5. Prepare a bottle of special accelerator cleaner.

6. Spray throttle cleaner along the circular hole of Audi A4L idle motor.

Seven, brush back and forth with a long brush.

Eight, after brushing, pour out the accelerator cleaner in the Audi A4L idle motor.

9. Just put the Audi A4L idle motor back to its original position.