1. Remove the air hose. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION.)
2. Disconnect the vacuum hose from the VTCS shutter valve actuator.

3. Connect a vacuum pump to the VTCS shutter valve actuator.
4. Apply vacuum and verify that the rod moves.

Variable intake-air system (vis) control solenoid valve inspection (l3)
Variable tumble control solenoid valve inspectionMazda 6 Service Manual: Intermittent concern troubleshooting
Vibration Method
1. If malfunction occurs or becomes worse while driving on a rough road or
when engine is vibrating, perform the steps below.
Note
There are several reasons vehicle or engine vibration could cause
an electrical malfunction. Some of the things to check for are:
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Mazda 6 Service Manual: System wiring diagram
ABS (ABS/TCS)
DSC
FOREWORD
Before performing the steps in Symptom Troubleshooting, perform the
On-board Diagnostic Inspection. To check the DTC, follow the DTC Inspection
steps.
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