Acceleration Mode; Deceleration Mode - Geely EC718 2009 Workshop Manual

Engine
2.3.3 System Working Principle
2.3.3.1 System Working Principle
Intake manifold absolute pressure sensor senses and
measures intake manifold vacuum. When the fuel demand is
high, the intake manifold absolute pressure in a low-vacuum
state, such as the throttle fully open. Engine control module
uses this information to enrich the mixture, thereby increasing
the fuel injector opening time and injecting the correct amount
of fuel. When the engine decelerates, the intake manifold
absolute pressure sensor detects increase in the vacuum
degree, the engine control module requests to shorten the fuel
injector opening time, reducing the amount of fuel injection
according to the change.
1. Startup Mode
When the ignition switch is turned on, the engine control
module connects to the fuel pump relay 2 s. Then, the fuel
pump fuel pressure is established. Engine control module also
Check the engine coolant temperature sensor and throttle
position sensor to determine the most appropriate Air-Fuel ratio
to start the engine. Engine control module controls the fuel
supply by changing the fuel injectors opening and closing time.
This is achieved by controlling the fuel injectors with very short
pulses.

2. Acceleration Mode

Engine control module responds to throttle position and the
rapid changes in airflow and provides additional fuel.

3. Deceleration Mode

Engine control module responds to throttle position and gas
flow rate changes and reduces the fuel amount. When the
speed rapidly decreases, the engine control module can
completely cut off fuel supply.
4. Battery Voltage Calibration Mode
When the battery voltage is too low, the engine control module
uses the following methods compensate for a weak ignition
spark:
–
Increase fuel injector pulse width.
–
Increase idle speed.
– Increase the ignition duration.
5. Stop Fuel Supply
When the ignition switch is turned off, the fuel injector will not
provide fuel. This prevents the continued combustion or engine
Fuel System JL4G18-D
can not shut down. In addition, if the reference pulse is not
received, there will be no fuel supply, in order to prevent fuel
overflow.
EC718/EC718RV EC715/EC715RV 10/2009
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