Variable Fresh Air Duct (Vfad) Actuator Construction/Operation (13B-Msp (High Power)); Variable Dynamic Effect Intake-Air (Vdi) Solenoid Valve Function; Variable Dynamic Effect Intake-Air (Vdi) Solenoid Valve Construction/Operation; Variable Dynamic Effect Intake-Air (Vdi) Actuator Function - Mazda RX-8 2004 Service Highlights

VARIABLE FRESH AIR DUCT (VFAD) ACTUATOR CONSTRUCTION/OPERATION (13B-MSP (HIGH POWER))

• A diaphragm design has been adopted.
• Normally, the rod is pushed by the force of the spring, opening the VFAD valve. When intake manifold vacuum
is applied to the diaphragm chamber, the rod is pulled, closing the VFAD valve.
End Of Sie

VARIABLE DYNAMIC EFFECT INTAKE-AIR (VDI) SOLENOID VALVE FUNCTION

• Switches pressure (intake manifold vacuum or BARO) applied to the VDI actuator according to a signal from
the PCM.
End Of Sie

VARIABLE DYNAMIC EFFECT INTAKE-AIR (VDI) SOLENOID VALVE CONSTRUCTION/OPERATION

• Composed of a solenoid coil, spring, plunger, and filter.
Energized
• When the solenoid coil is energized, the plunger is pulled back. Pulling the plunger back opens the
passage between ports A and B. Due to this, intake manifold vacuum is applied to the actuator.
De-energized
• Passage of port A is closed by the reaction force of the spring, and the passage between ports B and C is
opened. Due to this, BARO is applied to the actuator.
End Of Sie

VARIABLE DYNAMIC EFFECT INTAKE-AIR (VDI) ACTUATOR FUNCTION

• Opens and closes the VDI valve.
End Of Sie
INTAKE-AIR SYSTEM
VFAD VALVE
PULL
RETURN
(CLOSE)
(OPEN)
B
A
CHU011320130S04
01–13
VFAD ACTUATOR
CHU0113S020
CHU011318740S05
CHU011318740S06
C
CHU0113S017
CHU011320130S05
01–13–13