Idle Speed Control - Geely EC718 2009 Workshop Manual

Engine
3. Forced Idle Mode
When the driver's intention can not be reliably detected, such
as when the pedal signal is lost. The vehicle only maintains
cooling, heating, electricity supply and lighting functions with
engine idling. When pressing the acceleration pedal there is no
engine response, so in this mode the vehicle can not be driven.
4. Restricted Power Management Mode
ETC system can not use the throttle to control engine power.
In this mode, the system determines whether the engine is at
idle speed or is accelerating based on the acceleration pedal
signal. The system controls engine power output by shutting
down the engine, or by stopping a cylinder fuel injection, or by
delaying the ignition. The engine output fluctuation is obvious.
Working a long time in this mode would be harmful to the
engine emission system. The model ensures that the vehicle
can be driven, but difficult to control in normal driving or in traffic
or on a steep slope.
5. When the reliability of determining the drive intention
is decreased or when the system can not achieve high
power output
When the two acceleration pedal position sensors input signals
difference is too great, the engine's output torque is limited. The
engine's response to with the pedal position change is much
slower. The driver may feel that the engine power output will
be significantly weakened , but the vehicle will still be able to
drive in normal traffic.

2.12.3.5 Idle Speed Control

idle air flow control is that the engine control system maintains
the throttle body fully closed at target idle speed. The system
maintains a smooth transition with the throttle body fully closed
to prevent the stall. When the engine load changes at idle
speed, system maintains a steady engine speed.
Control System JL4G15-D
1. Target Idle Speed Calculating
Base Idle Speed
Speed
Compensation
Target Idle Speed
Calculation
Deceleration
Adjustment
Actual Idle Speed
2. The Basic Target Idle Speed
At different coolant temperatures, the basic target idle settings
are as following:
Coolant Temperature
(°C/ ºF)
＜ 20/-4
-10/14
0/32
10/50
20/68
30/86
40/104
50/122
60/140
70/158
80/176
90/194
EC718/EC718RV EC715/EC715RV 10/2009
2-597
Voltage
Compensation
Air Conditioning
Compensation
FE02-8040b
Target Idle Speed (rpm)
1,175
1,200
1,200
1,150
1,150
1,150
1,000
900
850
800
750
750