Toyota 2GR-FE Manual page 425

1. KEY-OFF MONITOR
5 hours* after the engine switch is turned off, the electric vacuum pump creates negative pressure
(vacuum) in the EVAP (Evaporative Emission) system. The ECM monitors for leaks and actuator
malfunctions based on the EVAP pressure.
HINT:
*: If the engine coolant temperature is not below 35°C (95°F) 5 hours after the engine switch is turned
off, the monitor check starts 2 hours later. If it is still not below 35°C (95°F) 7 hours after the engine
switch is turned off, the monitor check starts 2.5 hours later.
Sequence
- ECM activation
Atmospheric pressure
A
measurement
First 0.02 inch leak pressure
B
measurement
EVAP system pressure
C
measurement
D EVAP VSV monitor
Second 0.02 inch leak pressure
E
measurement
F Final check
HINT:
*: If only a small amount of fuel is in the fuel tank, it takes longer for the EVAP pressure to stabilize.
2GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM
Operation
Activated by soak timer, 5 hours (7 or 9.5 hours) after
engine switch turned off.
Vent valve turned OFF (vent) and EVAP system
pressure measured by ECM in order to register
atmospheric pressure.
If pressure in EVAP system not between 70 kPa and
110 kPa (525 mmHg and 825 mmHg), ECM cancels
EVAP system monitor.
In order to determine 0.02 inch leak pressure standard,
vacuum pump creates negative pressure (vacuum)
through 0.02 inch orifice and then ECM checks if
vacuum pump and vent valve operate normally.
Vent valve turned ON (closed) to shut EVAP system.
Negative pressure (vacuum) created in EVAP system,
and EVAP system pressure then measured.
Write down measured value as they will be used in leak
check.
If EVAP pressure does not stabilize within 15 minutes,
ECM cancels EVAP system monitor.
EVAP VSV opened and then EVAP system pressure
measured by ECM.
Large increase indicates normal.
After second 0.02 inch leak pressure measurement,
leak check performed by comparing first and second
0.02 inch leak pressure standards.
If stabilized system pressure higher than second 0.02
inch leak pressure standard, ECM determines that
EVAP system leaking.
Atmospheric pressure measured and then monitoring
result recorded by ECM.
Description
ES–269
Duration
-
10 seconds
ES
60 seconds
15 seconds*
10 seconds
60 seconds
-