VARIABLE INDUCTION AIR CONTROL SYSTEM (VIAS)
EC-633
C
D
E
F
G
H
I
J
K
L
M
A
EC
VARIABLE INDUCTION AIR CONTROL SYSTEM (VIAS)
PFP:14956
Description
EBS00MNQ
SYSTEM DESCRIPTION
When the engine is running at low or medium speed, the power valve is fully closed. Under this condition, the
effective suction port length is equivalent to the total length of the intake manifold collector's suction port
including the intake valve. This long suction port provides increased air intake which results in improved suc-
tion efficiency and higher torque generation.
The surge tank and one-way valve are provided. When engine is running at high speed, the ECM sends the
signal to the VIAS control solenoid valve. This signal introduces the intake manifold vacuum into the power
valve actuator and therefore opens the power valve to two suction passages together in the collector.
Under this condition, the effective port length is equivalent to the length of the suction port provided indepen-
dently for each cylinder. This shortened port length results in enhanced engine output with reduced suction
resistance under high speeds.
The power valve is always open regardless of the engine speed when gear position is in “N” or “P”.
COMPONENT DESCRIPTION
Power Valve
The power valve is installed in intake manifold collector and used to
control the suction passage of the variable induction air control sys-
tem. It is set in the fully closed or fully opened position by the power
valve actuator operated by the vacuum stored in the surge tank. The
vacuum in the surge tank is controlled by the VIAS control solenoid
valve.
Sensor
Input Signal to ECM
ECM function
Actuator
Mass air flow sensor
Amount of intake air
VIAS control
VIAS control solenoid valve
Throttle position sensor
Throttle position
Accelerator pedal position sensor
Accelerator pedal position
Ignition switch
Start signal
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)
Engine speed
Engine coolant temperature sensor
Engine coolant temperature
PBIB1876E
PBIB1253E