Toyota FJ Cruiser (GSJ 10, 15 series). Instruction - part 101
1GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM
ES–359
ES
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The 2nd monitor
The vent valve is turned OFF (open) and the EVAP pressure is measured. If the variation in the
pressure is less than 0.5 kPa-g (3.75 mmHg-g), the ECM interprets this as the purge VSV being
stuck closed, and illuminates the MIL and sets DTC P0441 (2 trip detection logic).
Atmospheric pressure check:
In order to ensure reliable malfunction detection, the variation between the atmospheric pressures, before
and after conduction of the purge flow monitor, is measured by the ECM.
Components
Operations
Canister
Contains activated charcoal to absorb EVAP (Evaporative Emissions) generated in fuel tank.
Cut-off valve
Located in fuel tank. Valve floats and closes when fuel tank 100 % full.
Purge VSV (Vacuum
Switching Valve)
Opens or closes line between canister and intake manifold. ECM uses purge VSV to control EVAP purge flow. In
order to discharge EVAP absorbed by canister to intake manifold, ECM opens purge VSV. EVAP discharge
volume to intake manifold controlled by purge VSV duty cycle ratio (current-carrying time). (Open: ON, Closed:
OFF)
Refueling valve
Controls EVAP pressure from fuel tank to canister. Valve consists of diaphragm, spring and restrictor (diameter:
0.08 inch). When fuel vapor and pressure inside fuel tank increase, valve opens. While EVAP purged, valve
closes and restrictor prevents large amount of vacuum from affecting pressure in fuel tank. Valve opened while
refueling.
Roll-over valve
Located in fuel tank. Valve closes by its own weight when vehicle overturns to prevent fuel from spilling out.
Soak timer
Built into ECM. To ensure accurate EVAP monitor, measures 5 hours (+-15 minutes) after ignition switch turned
OFF. This allows fuel to cool down, stabilizing EVAP pressure. When approximately 5 hours elapsed, ECM
activates (refer to fig. 3).
Canister pump module
Consists of (a) to (d) below. Canister pump module cannot be disassembled.
(a) Vent valve
Vents and closes EVAP system. When ECM turns valve ON, EVAP system closed. When, ECM turns valve OFF,
EVAP system vented. Negative pressure (vacuum) created in EVAP system to check for EVAP leaks by closing
purge VSV, turning on vent valve (closed) and operating leak detection pump (refer to fig. 1).
(b) Canister pressure
sensor
Indicates pressure as voltages. ECM supplies regulated 5 V to canister pressure sensor, and uses feedback from
sensor to monitor EVAP system pressure (refer to fig. 2).
EVAP Purge Flow:
Fuel Cap
Canister Pressure Sensor
Reference Orifice (0.02 inch)
Refueling Valve
To Atmosphere
Vent Valve (OFF)
Canister Pump Module
Canister Filter
Fuel Tank
Soak Timer
To Intake Manifold
ECM
Leak Detection Pump (OFF)
Purge VSV
(ON)
Canister
A122571E02