Ford Corsar Repair Manual page 258

E.C.C.S. DESCRIPTION
-
E.C.C.S. Components
pq
(Through idle
(Through
A.A.C. valve)
Coolant
ldle adjusting
screw
Air
C
Engine coolant
O R =
A
SEF1221
L
ldle Air Adjusting (I.A.A.) Unit
The I.A.A. unit is made up of the A.A.C. valve and air cut valve.
It receives the signal from the E.C.U. and controls the idle speed
at the preset value under various conditions.
The air cut valve prevents an abnormal rise of idle rpm when
A.A.C. valve operates abnormally.
Auxiliary Air Control (A.A.C.) Valve
The E.C.U. actuates the A.A.C. valve by an ONIOFF pulse. The
From power
7
valve housing
longer that ON pulse is received, the larger the amount of air
that will flow through the A.A.C. valve.
This air flow also varies with the temperature of the engine
coolant flowing through the A.A.C. valve. The higher the coolant
temperature, the less the amount of air flow.
Power Steering Oil Pressure Switch
The power steering oil pressure switch is attached to the power
steering high-pressure tube and detects the power steering
load, sending the load signal to the E.C.U. The E.C.U. then
sends the idle-up signal to the A.A.C. valve.
Vehicle Speed Sensor
The vehicle speed sensor provides a vehicle speed signal to the
E.C.U.
Carbon Canister Purge (C.C.P.) Control Solenoid
Valve
The C.C.P. system is controlled by the E.C.U. At both low- and high-
speed engine revolutions, the solenoid valve turns "ON" to
de-activate the system.