Chery A11. Manual — part 108

Part MOT multi-port electric fuel injection engine system

SQR480EC electric fuel injection system

I. System

description

Electric fuel injection system is a complete functions system and mainly consists of fuel

system, air system and electric control system. It also includes ignition control and

exhaust control functions etc.

Fuel system

Fuel passes through fuel tank built-in oil pump to fuel filter, and is pressed to oil rail after

filtering, then sprayed into cylinder via fuel injector, and then returns to fuel tank through fuel

pressure adjuster, which can maintain constant fuel pressure. Fuel injector locates at the air

intake port of each cylinder and spray fuel into cylinder.

Air system

Air system includes air intake system air cleaner, air pressure sensor, temperature sensor,

throttle valve body, air intake hose and manifold, and idle adjuster valve and idle adjuster

screw for idle adjusting.

Electric Control System

Consists of sensor, ECU and actuator, including ECU, air intake temperature and pressure

sensor, water temperature sensor, throttle valve position sensor, oxygen sensor, electric oil

pump, fuel injector, ignition coi land throttle valve body etc.

13 Oil pressure adjuster

14 Oxygen sensor

15 3-way catalyst converter

Engine coolant temperature sensor (water

temperature sensor)

17 Crankshaft position RPM sensor

18 ECU

19 Battery

20 Electric fuel injector

21 Pressure switch

22 Ignition switch

23 A/C compressor

1 Fuel Vapor Tank (carbon canister)

Oil pump

Fuel tank

Engine

Fuel rail

Air Intake Temperature And Pressure Sensor

Air cleaner

Idle step motor

Throttle position sensor

Throttle valve body

Spark Plug 12 Ignition coil

II. Operation

SQR480EC electric fuel injection system controls ignition, fuel injection, idle ect. upon

engine speed signal, air intake pressure, throttle position signal, air temperature signal,

oxygen sensor signal and coolant temperature signal. The system utilize an advanced

control strategy, and selected components and a complete set of strict production process,

and is an electric fuel injection system featuring intelligence and stability, meets the strict

technological demands of car manufacturer with the exhaust meeting the Euro II standard.

The fuel system offers a 2.5 Bar fuel supply pressure.

2.1 electric control system

2.1.1 ECU

Parameter

Unit Minimum

Maximum

Operating

voltage

Volt 6.5 16

Operating

current

Ampere 0.01

0.1

Operating

temperatu

re

Centigrade

-40 85

Humidity

%RH 20 85

Vibrating

frequency

HZ … 1000

ECU operation ambient temperature range is -40℃---+85℃, therefore, before baking

varnish for the automobile body, it should be removed first, and the temperature should be

under strict control to avoid ECU being damaged.

2. ECU damage has a low damage probability (damage ratio less than 1/1000 after 100000

KM mileage) and do not suspect the ECU damage. Even ECU damage is suspected, do not

attempt to disassemble it (replace the internal core) because a defective ECU can not be

repaired.

EI system wiring harness

For MPI-ECU wiring harness assembly (multi-port fuel injection---ECU wiring harness),

see illustration.

Engine wiring harness

See illustration.

Water Temperature Sensor

Sensor has 2 leads, one is signal lead (pin B10) and the other is ground lead (pin B23)

Water

Temperature

Ohm

●Measuring Method

a ohmmeter method

Measure resistance with an ohmmeter, and determine if water temperature sensor operates

upon measured engine coolant temperature and below diagram. Remove coolant

temperature sensor, immerse into water and heat water. The sensor has different resistance

at corresponding temperature.

Water Temperature Sensor Resistance Specification

Temperature(℃)

Resistance(Ω)

Temp.(℃)

Resistance(Ω) Temp.(℃)

Resistance(

-40 100865

25

2795

90

241.8

-35 72437

30

2240

95

207.1

-30 52594

35

1806

100

178.0

-25 38583

40

1465

105

153.6

-20 28582

45

1195

110

133.1

-15 21317

50

980

115

115.7

-10 16120

55

809

120

100.9

-5 12261

60

671

125

88.3

0 9399

65

559

130

77.5

5 7263

70

469

135

68.3

10 5658

75

395

140

60.3

15 4441

80

334

145

53.4

20 3511

85

283

150

47.5

b voltmeter method

Install the sensor on the motor, and crank engine. Connect sensor signal lead to

voltmeter, there are different voltage drop at different temperature.

Oxygen sensor

Oxygen sensor is installed on exhaust pipe and accurately regulate excess air co-efficiency .

Oxygen sensor has 4 leads: C. voltage lead (pin A16) B. signal lead (pin B1)

A. signal ground (pin B23) D heater ground (pin B16)

PIN Function

C Sensor

voltage lead

B Sensor

signal

output

A Signal

ground

D Heater

ground

Oxygen sensor heater resistance impedance specification table

when temperature is 23℃, impedance is

13.2+/-10%

Resistance Heat Co-efficiency of

impedance

(23-800℃) (ppm/℃)

1150