
Diagnostic procedure

Dtc p0661
Dtc p0703Mazda 6 Service Manual: Nonreturn valve inspection
1. Remove the fuel pump unit. (See FUEL PUMP UNIT REMOVAL/INSTALLATION.)
2. Siphon the fuel from the fuel tank.
Note
Nonreturn valve is integrated in the fuel tank.
The nonreturn valve is normally closed by the spring force.
3. Verify that the nonreturn valve is closed.
If the nonretu ...
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 ...