Daihatsu F300 Service Manual page 1348

• CHOKE BREAKER SYSTEM
•
•
•
This system opens the choke valve during a period immediately
after starting so as to reduce the HC and CO emissions.
Operation
During a period immediately after starting, negative pressure
is applied gradually to the first stage of the choke breaker
diaphragm. Consequently, the choke valve is opened slightly.
When the water temperature is low, the atmosphere is applied
to the second stage of the choke breaker diaphragm via the
TVSV. Thus, the second diaphragm remains inoperative.
When the temperature reaches a certain level as the cooling
water temperature rises. the negative pressure of the intake
manifold starts to be applied to the second stage of the choke
breaker diaphragm via the TVSV .
As a result, the choke valve opens further, thereby preventing
the air-to- fuel ratio from becoming too rich.
Switching Ternperature of TVSV
Inspection of choke breaker system
1.
Inspection of
TVSV
with cold engine
( 1) Start the engine.
(2) With the coolant temperature below 15°C, disconnect
the vacuum hose from choke breaker diaphragm Band
check that the choke linkage does not move.
(3) Reconnect the vacuum hose to diaphragm B.
2. Inspection of jet and diaphragm A
(1) Disconnect the vacuum hose from the choke breaker
diaphragm
A
and check linkage moves.
(2) Reconnect the vacuum hose to diaphragm A and check
that the choke linkage moves within the specified time
after reconnecting
the
hose.
Specified
lime: 1 - 5
seconds
EC-9
EMISSION CONTROL SYSTE"~