Variable Dynamic Effect Intake-Air (VDI) Actuator Inspection

WARNING: This page is about a different car, the 2004 Mazda RX-8. However, it is still accessible from the selected car via links, so may be relevant.

Disconnect the VDI actuator vacuum hose.
Install the vacuum pump to the VDI actuator.
Verify that the rod moves as indicated in the figure below when gradually applying a vacuum to the VDI actuator. See Fig 1 .
- If it fails, replace the VDI actuator. (See INTAKE MANIFOLD REMOVAL/INSTALLATION .)
Rod movement

Fig 1: Variable Dynamic Effect Intake-Air Actuator Inspection Rod Movement
Courtesy of MAZDA MOTORS CORP.

Fig 2: Applying Vacuum To VDI Actuator For Rod Movement
Courtesy of MAZDA MOTORS CORP.