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: Front door key cylinder removal/installation
1. Remove the front door unit.
2. Remove the cover, then remove the bolt.
3. For protector-equipped vehicles, pull out the protector tab from the latch
and remove the protector.
4. Disconnect the rod.
5. Remove the front outer handle.
6. Turn the key cylinder in the direction indicated by ...
Mazda 6 Service Manual: Air intake actuator inspection
1. Connect battery positive voltage to terminal D or F and ground to terminal
F or D of the air intake actuator.
2. Verify that the air intake actuator operates as shown below.
If not as specified, replace the air intake actuator.
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