Toyota 1NZ-FE, Руководство пользователя

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ENGINE - 1NZ-FE ENGINE
D13N20
Purge
VSV ON (Open)
OFF (Close)
Vent
Valve
ON
OFF (Vent)
ON
OFF
Atmospheric Pressure
Pump Motor
System
Pressure
0.02 in. Pressure
1) 2) 3) 4) 5)
EG-51
3) EVAP Leak Check
a. General
The EVAP leak check operates in accordance with the following timing chart:
Timing Chart
Order Operation Description Time
1)
Atmospheric Pressure
Measurement ECM turns vent valve OFF (vent) and measures EVAP
system pressure to memorize atmospheric pressure.
10 sec.
2)
0.02 in. Leak
Pressure
Measurement
Leak detection pump creates negative pressure
(vacuum) through 0.02 in. orifice and the pressure is
measured. ECM determines this as 0.02 in. leak
pressure.
60 sec.
3) EVAP Leak Check
Leak detection pump creates negative pressure
(vacuum) in EVAP system and EVAP system pressure
is measured. If stabilized pressure is larger than 0.02 in.
leak pressure, ECM determines EVAP system has a
leakage. If EVAP pressure does not stabilize within 12
minutes, ECM cancels EVAP monitor.
Within
12 min.
4) Purge VSV Monitor
ECM opens purge VSV and measure EVAP pressure
increase. If increase is large, ECM interprets this as
normal.
10 sec.
5) Final Check
ECM measures atmospheric pressure and records
monitor result.
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