Mazda 6 Service Manual: No.20 noise occurs at idle when vehicle is stopped in all positions/ranges
Diagnostic procedure
Other materials:
Mazda 6 Service Manual: Variable intake-air system (vis) shutter valve actuator inspection (l3)
1. Remove the air hose. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION.)
2. Disconnect the vacuum hose from the VIS shutter valve actuator.
3. Connect a vacuum pump to the VIS shutter valve actuator.
4. Apply vacuum and verify that the rod moves.
If the rod dose not move, replace the intake ma ...
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 ...