Variable Intake-Air System (VIS) Inspection

Start engine.
Inspect rod operation. See VIS SHUTTER VALVE ROD OPERATION - MAZDA6 (2.3L) table. If shutter valve actuator rod operation is not as specified, inspect as follows:
- Stop engine.
- Connect scan tool to DLC-2.
- Ensure DTC P0661 or P0662 is not displayed. If DTC P0661 or P0662 is displayed, see appropriate DTC testing procedure under DIAGNOSTIC TESTS in SELF-DIAGNOSTICS - MAZDA6 2.3L article.
- Check VIS control solenoid valve. See VARIABLE INTAKE-AIR SYSTEM CONTROL SOLENOID VALVE INSPECTION . If VIS control solenoid valve is faulty, replace VIS control solenoid valve. If VIS control solenoid valve is okay, check following:
  1. Vacuum hose and vacuum chamber for looseness or damage.
  2. VIS shutter valve actuator. See VARIABLE INTAKE-AIR SYSTEM (VIS) SHUTTER VALVE ACTUATOR INSPECTION .
  3. Check if VIS shutter valve is stuck open or closed.
  Repair as necessary.

VIS SHUTTER VALVE ROD OPERATION - MAZDA6 (2.3L)

Engine RPM	Shutter Valve Operation
Less Than 4500	Operates
More Than 4500	Does Not Operate