Mazda 6 Service Manual: No.22 vibration concerns (engine)

No.21 engine noise

No.23 a/c does not work sufficiently

Other materials:

Mazda 6 Service Manual: Recommendations for Shifting
Upshifting For normal acceleration and cruising, Mazda recommends these shift points: *1 Always observe local speed limit regulations. Downshifting When you must slow down in heavy traffic or on a steep upgrade, downshift before the engine starts to overwork. This gives better acceleration w ...

Mazda 6 Service Manual: No.9 noise while operating a/c system
Diagnostic procedure * : If there is gas leakage, air enters into the A/C system. The desiccant within the receiver/drier absorbs the moisture from the air and becomes saturated. If the A/C system is used in this condition, the inside of the A/C compressor will begin to rust due to this ...