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: Recommended Oil
U.S.A. and CANADA Use SAE 0W-20 engine oil. Mazda Genuine Oil is used in your Mazda vehicle. Mazda Genuine 0W-20 Oil is required to achieve optimum fuel economy. For maintenance service, Mazda recommends Mazda Genuine Parts and Castrol® (U.S.A. only). Only use SAE 0W-20 oil “Certified F ...

Mazda 6 Service Manual: Knock sensor inspection
Note Perform the following test only when directed. Resistance Inspection 1. Turn the ignition switch to LOCK. 2. Disconnect the knock sensor connector. 3. Measure the resistance between the knock sensor terminals A and B using an ohmmeter. If not as specified, replace the knock sens ...