Honda Civic Service Manual page 243

Fuel and Emissions Systems
System Descriptions (cont'dl
ldle Control System Diagram
The idle speed of the engine is controlled by the ldle Air Control (lAC) varve:
' A f t e r t h e e n g i n e s t a r t s , t h e I A C v a l v e o p e n s f o r a c e r t a i n a m o u n t o f t i m e . T h e a m o u n t o f a i r i s i n c r e a s e d t o r a i s e t h e
i d l e s D e e d .
. When the engine coolant temperature is low, the IAC valve is opened to obtain the proper fast idle speed. The
amount of bypassed air is controlled in relation to engine coolant temperature.
INTAKE MANIFOLD
IAC VALVE AKE AIR DUCT
C L E A N E R
\
BLK/
R E O
YEL/BLK ---<
From
PGM.FI
M A I N
RELAY
THROTTLE AODY
Intake Air System Diagram
This system supplies air for engine needs. A resonator in the intake air
drawn into the svstem.
VARIOUS
SENSOnS
pipe provides additional silencing as air is
THROTTLE AODY
VARIOUS
SENSORS
BLK
BLK
I
1 1 - 3 6
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