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: Variable valve timing actuator removal/installation
L3 Caution Variable valve timing actuator can not be disassembled because it is a precision unit. Note Variable valve timing actuator camshaft sprocket is integrated with the variable valve timing actuator and cannot be disassembled. 1. Follow the timing chain removal/installati ...

Mazda 6 Service Manual: Engine coolant temperature (ect) sensor inspection
Note Perform the following inspection only when directed. ECT Sensor Resistance Inspection 1. Drain the engine coolant. (See COOLING SYSTEM SERVICE WARNINGS.) 2. Remove the ECT sensor (located above the starter). 3. Place the ECT sensor in water with a thermometer, and heat the water gra ...