Mazda 323 1988 Workshop Manual page 304

46
IDLE SPEED CONTROL (ISC) SYSTEM
IDLE SPEED CONTROL (ISC) SYSTEM
Dashpot
I
Throttle sensor
Engine control unit
E/L control unit
Water therm.0 sensor
1 / Nebtral &itch
OUTLINE
To improve idle smoothness, the ISC system controls the intake air amount detected by the air flow
meter by regulating the bypass air amount that passes through the throttle body, and thereby helps
the engine to maintain a steady idle speed.
This system consists of the BAG valve and the control system.
The BAC valve consists of the air valve which functions only during cold engine conditions and the
ISC valve which works throughout the entire engine speed range.
48-32
323
Revised 10187