Mazda 6 Service Manual: No.20 noise occurs at idle when vehicle is stopped in all positions/ranges

No.19 excessive shift shock on torque converter clutch (tcc)

No.21 noise occurs at idle when vehicle is stopped in d, s, l ranges, or in r position

Other materials:

Mazda 6 Service Manual: To Resume Cruising Speed at More Than 25 km/h (16 mph)
If some other method besides the OFF/ CANCEL switch was used to cancel cruising speed (such as applying the brake pedal) and the system is still activated, the most recent set speed will automatically resume when the RESUME/ switch is pressed. If vehicle speed is below 25 km/h (16 mph), incre ...

Mazda 6 Service Manual: Variable air duct (vad) control solenoid valve inspection (l3)
1. Remove the VAD control solenoid valve. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION.) 2. Inspect airflow between the ports under the following conditions. If not as specified, replace the VAD control solenoid valve. If as specified, carry out the Circuit Open/Short Inspection. Circ ...