1. Verify that the joint shaft is not twisted or cracked.
2. Turn the joint shaft by hand and verify that the bearing rotates smoothly and freely.

Drive shaft
Joint shaft removal/installationMazda 6 Service Manual: Flasher unit inspection
1. Connect the connector to the flasher unit.
2. Connect the negative battery cable.
3. Measure the voltage at the flasher unit using voltmeter.
When inspecting terminal F for continuity, disconnect the flasher unit connector.
4. If the value are not as specified in the Terminal Voltag ...
Mazda 6 Service Manual: Engine Exhaust (Carbon monoxide)
WARNING
Do not drive your vehicle if you smell exhaust gas inside the vehicle:
Engine exhaust gas is dangerous. This gas contains carbon monoxide (CO), which is
colorless, odorless, and poisonous. When inhaled, it can cause loss of consciousness
and death. If you smell exhaust gas inside the ...