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: Fuel Requirements
Vehicles with catalytic converters or oxygen sensors must use ONLY UNLEADED FUEL, which will reduce exhaust emissions and keep spark plug fouling to a minimum. This vehicle will perform best with fuel listed in the table. * U.S. federal law requires that octane ratings be posted on gasoline st ...

Mazda 6 Service Manual: Jam-safe Moonroof
If a person's hands, head or an object blocks the moonroof while it is closing, the moonroof will stop and move in the reverse direction. WARNING Make sure nothing blocks the moonroof just before it reaches the fully closed position: Blocking the moonroof just before it reaches the closed posi ...