Geely EC718, EC718RV, EC715, EC715RV. Manual part — 170

A. Air-Fuel Ratio

Start Air-Fuel ratio, normal start Air-Fuel ratio, clear the
flooded cylinder Air-Fuel ratio, engine running Air-Fuel
ratio, cooling state Air-Fuel ratio, warm-up state Air-Fuel
ratio, theoretical Air-Fuel ratio, power-enriched Air-Fuel
ratio, catalytic overheating protection Air-Fuel ratio, engine
overheating protection Air-Fuel ratio.

B. Intake Manifold Absolute Pressure

Intake manifold absolute pressure is detected by the MAP
sensor installed on the intake manifold.

C. Volumetric Efficiency

Volumetric efficiency is the actual air flow into the cylinder
to the ideal air flow ratio.

D. Phase Volumetric Efficiency

The valve timing changes affect the engine's volumetric
efficiency. The basic efficiency table is set when the valve
timing control system has not started to work, the camshaft
and the crankshaft are at initial positions. When the valve
timing control system starts to work, the system will
compensate the volumetric efficiency to ensure an accurate
calculation of air flow.

E. Self Learn

self learn does not amend the changes as the engine
running time increases, or the engine and vehicle
manufacturing errors.

F. Close-loop Feedback Correction

Close-loop feedback correction controls the actual Air-Fuel
ratio close to the theoretical Air-Fuel ratio through the
oxygen sensor feedback signals.

G. Transition Condition Fuel Control

System uses more complex algorithms to establish the fuel
evaporation model to calculate Air-Fuel mixing conditions,
taking into account the engine coolant temperature, intake
air temperature and engine working condition and the best
fuel injection amount. It greatly improves fuel control under
various transitional working conditions, including sudden
acceleration/ deceleration and other working conditions.

H. Protective Fuel Supply Control

When any one of the following conditions is met, the system
will stop fuel injection:

–

When the engine speed is higher than 6,400 rpm,
resume fuel supply when the engine speed drops below
6,000 rpm.

–

When the system detects a ignition system malfunction,
it stops the fuel supply.

–

When the system voltage is greater than 18 V, it will
enter the electronic throttle body function restriction
mode (forced idle mode).

I. Basic Fuel Injection Constant

The basic fuel injection constant provides engine
displacement and the fuel injector fuel flow rate
relationship.

J. Battery Voltage Amendment

When the battery voltage changes, voltage is amended to
ensure the correct amount of fuel injection.

2.12.3.3 ECM Controlled Ignition System

1. Closed Ignition Angle Control

The length the ignition angle closes determines the spark plug
ignition energy. Ignition coil magnetizing too long will damage
the coil or ECM internal ignition coil driver circuit, while too short
will cause ignition failure (misfire).

2. Starting Mode

In the starting mode, the system uses a fixed ignition angle in
order to ensure cylinder mixture is ignited, and provide positive
torque. When the engine starts to run, the engine speed
increases. The ignition angle will no longer be in starting mode.

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3. Ignition Advance Angle Calculation and Control

Ignition Angle

Ignition Advance

Angle Calculation

Ignition

Advance Angle

Coolant Temperature

Compensation

Air Temperature

Compensation

Valve Position

Compensation

Acceleration

Compensation

Idle Compensation

Ignition Advance

Angle Compensation

Air Conditioning

Compensation

Enrich

Deceleration

Compensation

FE02-8039b

A. Main Ignition Advance Angle

When the engine temperature is normal, with the throttle
opening, the main ignition angle is the minimum ignition
angle with the optimal torque or the threshold of detonation.
When the throttle is closed, the ignition angle should be less
than optimal torque point for idle stability.
Without affecting driving with a cold engine, in order to
reach the normal operating temperature as quickly as
possible, in the catalytic converter heating process, the
basic ignition angle can be angle other than the minimum
ignition angle with the optimal torque or the threshold of
detonation. This angle should also be delayed as much as
possible without affecting the driving ability.

B. Ignition Advance Angle Adjustment

temperature

adjustment,

intake

air

temperature

adjustment, altitude compensation adjustment, idle speed
adjustment, power-enriched adjustment, deceleration fuel
supply adjustment, Air-Conditioning control adjustment,
exhaust gas recirculation adjustment.

C. Acceleration Adjustment

Ignition advance angle acceleration adjustment is used to
mitigate the drive system torque shock caused by engine
speed fluctuations, and also to eliminate possible
detonation during acceleration, so that the acceleration is
smooth.

D. Valve Timing-controlled Ignition Angle Compensation

In order to obtain a better power and torque, system will
enrich the Air-Fuel ratio to achieve the optimal torque and
adjusts the ignition advance to achieve the optimal torque
output.

E. Valve Timing-controlled Ignition Angle Compensation

When the valve timing control system works, the engine's
intake and exhaust overlap angle change will affect the
internal exhaust gas recirculation rate and the cylinder
temperature. According to different valve timing, system
needs to adjust ignition advance angle to ensure that under
current valve timing, the actual ignition advance angle is the
best.

F. Deceleration Fuel Supply Adjustment

When the system exits the deceleration fuel supply control
mode, the ignition angle will be adjusted to make the throttle
closing transition smooth.

G. Air-Conditioning Control Adjustment

When the engine is idling, the Air-Conditioning is turned off.
The ignition angle will be adjusted to make the engine run
smoothly.

2.12.3.4 Electronic Throttle Body Function
Restrictions

1. Forced Shut Down

When ECM reports a malfunction, intake or throttle air flow
control has a malfunction. The control strategy is to stop the
fuel supply, stop the ignition and close the throttle and shut
down the engine.

2. Forced Idle Power Management Mode

When the engine is idling, ETC system can not reliably use the
throttle to control engine power. At this point ETC cancels the
throttle control. The throttle opening is at the default position.
The engine power control is achieved by stopping one cylinder
fuel injection and delaying the ignition angle.

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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.

1. Target Idle Speed Calculating

Base Idle Speed

Target Idle Speed

Calculation

Actual Idle Speed

Speed

Compensation

Deceleration

Adjustment

Voltage

Compensation

Air Conditioning

Compensation

FE02-8040b

2. The Basic Target Idle Speed

At different coolant temperatures, the basic target idle settings
are as following:

Coolant Temperature

(°C/ ºF)

Target Idle Speed (rpm)

＜

20/-4

1,175

-10/14

1,200

0/32

1,200

10/50

1,150

20/68

1,150

30/86

1,150

40/104

1,000

50/122

900

60/140

850

70/158

800

80/176

750

90/194

750

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Coolant Temperature

(°C/ ºF)

Target Idle Speed (rpm)

100/212

750

110/230

750

>?20/248

800

3. Vehicle Speed Compensation and Deceleration
Speed Adjustment

To improve the deceleration and stop driving performance,
when the vehicle is driving, the target idle speed increases by
100 rpm higher than stopping idle speed. During the
deceleration and stopping, the speed gradually decreases to
the parking target idle speed.

4. Air-Conditioning Compensation

When the air-conditioning is turned on with the vehicle parking,
in order to compensate for the compressor power
consumption, when the coolant temperature is below 0°C / 32F,
the target idle speed increases by 50 rpm; when the coolant
temperature is above 0°C / 32F, the target idle speed increases
by 200 rpm.

5. Voltage Compensation

When the system voltage is lower than 11.5 V, and not restored
in 10 s, the system will increase the target idle speed by 250
rpm, in order to increase the amount of electricity generated.

When the external power load impacts the system, the
transient voltage will fluctuate. The system will automatically
compensate for the air flow rate in order to curb the engine
speed fluctuations.

2.12.3.6 Knock Control

Knock control is used to eliminate engine detonations that may
occur during the combustion to optimize engine power and fuel
economy. System can control different cylinder knocking
independently.

1. Knock Control Enable Conditions

–

The engine running time is longer than 2 s.

–

The engine coolant temperature is higher than 70°C /158 ºF

–

The engine speed is greater than 800 rpm .

2. Knock Control Mode

When a knocking occurs or is likely to occur, the system will
quickly delay the ignition advance angle. System-based spark

advance angle is either normal ignition advance angle or safety
ignition advance angle. Knock controlled speed is between
thees two.

–

Steady-State Control

When the engine is running as per normal, ECM collects
and analyzes engine combustion signals filters knocking
signal through the knock sensor. Once the knock intensity
is higher than the acceptable limit, the system will rapidly
delay the ignition advance angle cylinder in which the
detonation happened, to eliminate detonation in the
following combustion. The ignition advance angle will be
back to normal angle gradually.

–

Transient Control

During a sudden acceleration or a engine sudden speed
change, detonation is likely to happen. The system predicts
the likelihood of detonation, and automatically delays the
ignition advance angle in order to avoid a strong detonation.

–

Rapidly Delayed Ignition Advance Angle

Once the system detects a detonation, according to
different engine speeds, the system rapid delays ignition
advance angle 3-5 degrees, and resumes to normal
controls in 2-3 s afterward.

–

Adaptive Ignition Advance Angle

Due to wear and tear after long-term use, there are
differences between the engines. When the system and the
engine are in initial use or ECM is supplied with power, the
engine detonation may occur. The system will record the
detonation, after a period of running, the system will
automatically generate an adaptive adjustment value of the
ignition (self learn value). When the engine is running in the
same conditions, the system will automatically advance the
ignition angle, to the detonation occurring.
System adaptive learn process is constantly updated with
the engine running.

2.12.3.7 Air-Conditioning Switch Off Control

In some cases, in order to ensure the engine power or protect
the engine or protect the Air-Conditioning system, ECM must
stop the Air-Conditioning compressor working or prohibit the
Air-Conditioning system to start. At the same time to prevent
the compressor clutch and frequently on-off, once the system
enters into the Air-Conditioning switch off mode, ECM delays
for a specified period of time to control Air-Conditioning clutch
pull-in.

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