JAC S2. Engine. Instruction — part 16

Engine Auxiliary Emission System

Engine Mounting system
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Engine Auxiliary Emission System

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VIII、Connecting Hose of PCV Valve

(I)Removal

1. Open engine compartment cover

2. Disconnect battery negative electrode Refer to “Disconnection and connection of battery electrode”

3. Remove connecting hose of PCV

1). Disconnect connection of connecting hose of PCV valve and
PCV vlave;

2). Disconnect connection of connecting hose of PCV valve and
intake manifold, and take down connecting hose of PCV valve;

(II)Check

1. Check connecting hose of PCV valve

1). Check whether hose and hose connector is leaking;

2). Disconnect all hoses and clean with compressed air. If can’t clear obstruction in hose, please replace.

(III)Installation

1. Install connecting hose of PCV valve

1). Connect connecting hose of PCV valve and intake manifold;

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2). Connect connecting hose of PCV valve and PCV valve;

2. Connect battery negative electrode

3. Close engine compartment cover

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IX、Vacuum Boost Connecting Hose

(I)Removal

1. Open engine compartment cover

2. Disconnect battery negative electrode Refer to “Disconnection and connection of battery electrode”

3. Remove air filter assembly air filter assembly Refer to ““ air filter assembly

4. Remove vacuum boost connecting hose

1). Remove fixed clamp of vacuum boost connecting hose and

intake manifold;

2). Remove connecting clamp of vacuum boost connecting

hose and vacuum boost steel pipe;

3). Take down vacuum boost connecting hose;

(II)Installation

1. Install vacuum boost connecting hose

1). Connect vacuum boost connecting hose and vacuum boost

steel pipe;

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2). Connect vacuum boost connecting hose and intake

manifold;

2. Install air filter assembly

3. Connect battery negative electrode

4. Close engine compartment cover

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X、Vacuum Boost Steel Pipe

(I)Removal

1. Open engine compartment cover

2. Disconnect battery negative electrode Refer to “Disconnection and connection of battery electrode”

3. Remove air filter assembly Refer to “air filter assembly”

4. Remove vacuum boost steel pipe

1). Remove connecting clamp of vacuum boost connecting

hose and vacuum boost steel pipe, and disconnect vacuum

boost hose;

2). Remove fixed bolt of vacuum boost steel pipe and engine

shackle;

3). Remove fixed bolt of vacuum boost steel pipe and

cylinder head;

4). Disconnect connection of vacuum boost steel pipe and

vacuum hose;

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5). Disconnect knock sensor;

6). Take down vacuum boost steel pipe;

(II)Installation

1. Install vacuum boost steel pipe

1). Connect knock sensor connector to vacuum boost steel

pipe;

2). Connect connection of vacuum boost steel pipe and vacuum

hose;

3). Install fixed bolt of vacuum boost steel pipe and cylinder

head;

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4). Install fixed bolt of vacuum boost steel pipe and engine

shackle;

5). Connect vacuum boost steel pipe and vacuum boost

connecting hose, and tighten clamp;

2. Install air filter assembly

3. Connect battery negative electrode

4. Close engine compartment cover

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XI、Ventilator Ventilation Hose

(I)Removal

1. Open engine compartment cover

2. Disconnect battery negative electrode Refer to “Disconnection and connection of battery electrode”

3. Remove ventilator ventilation hose

1). Disconnect connection of ventilator ventilation hose and air

filter outlet pipe assembly;

2). Disconnect connection of ventilator ventilation hose and

cylinder head cover;

3). Take down ventilator ventilation hose;

(II)Installation

1. Install ventilator ventilation hose

1). Connect ventilator ventilation hose and cylinder head

cover;

2). Install ventilator ventilation hose and air filter outlet pipe

assembly;

2. Connect battery negative electrode

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3. Close engine compartment cover

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Engine Control System

I、Summary

(I)Structure Overview

Electrical Control System Constitution Function

Engine electrical control system is generic terms of all electronic control device installed in engine (or connected to engine), its

function is to control operation of all engine systems to make engine have well power performance, fuel economy and emission

performance.

Engine electrical control system is consist of three parts, namely sensor, ECM and actuator. ECM is the control center of engine

electrical control system, all sensors in engine electrical control system measure parameters of engine speed, throttle valve opening

degree, coolant temperature, intake temperature, analyze, judge and calculate according to setting program in ECM, and send out

instruct signal to actuators of fuel injector, ignition coil, fuel injector, OCV valve according to calculated result, to control all systems

operation of engine.

Control range of control system has already extended to all systems of engine fuel injection system, ignition system, intake

system, emission system. Therefore, control system can be consisted of fuel control system, ignition control system, intake control

system, emission control system, fault self-diagnosis system, crankshaft ventilation system according to its control function.

(II)System Principle

Engine Control System Structure

1. Carbon canister 10. Rear oxygen sensor
2. Carbon canister electromagnetic valve 11. Engine coolant temperature sensor
3. Electronic throttle valve assembly 12. Crankshaft position sensor
4. Intake pressure temperature sensor 13. Fuel filter
5. Fuel injector 14. Electrical power fuel pump

Engine control system

diagram

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6. Camshaft position sensor 15. Fuel tank
7. Ignition coil 16. Diagnosis connector
8. Front oxygen sensor 17. Engine Control Module
9. Three-way catalytic converter

On Vehicle Diagnosis System

1. Instruction

On vehicle diagnosis system (shorted from OBD system), is integrated in engine control system, and it’s a diagnosis system that

can monitor faulted components which influence exhaust gas emission and engine main function state. It has the function of

identification, storage and displaying fault information by self-diagnosis malfunction indicating light (MIL).

2. Function Introduction

Function of diagnosis system mainly has monitoring function, storing fault code and note function, lose efficacy protection

function and data output function.

(1)Monitoring Function

Objects of diagnosis system mainly are sensors, actuators in electrical control system and control process of electrical cont rol

system, fault self-diagnosis system monitors electrical control system related signal when vehicle is running, when some signal exceed

pre-setting range, and this phenomenon don’t disappear in some time, fault self-diagnosis system judges related circuit or component

of the signal has fault.

(2)Storing Fault Code and Note Function

Once fault self-diagnosis system detecting there is fault in electrical control system, fault indicating light in meter will be on,

remaindering driver to go to 4S shop to check and maintain, to avoid more damage.

Fault self-diagnosis system will monitor fault content and store in ECM memorizer in fault code. When maintaining, maintenance

personal can read fault code stored in ECM to supply accurate basis for finding faulted components.

(3)Lose Efficacy Protection Function

To different monitoring object, fault self-diagnosis system will adopt different lose efficacy protection mode when detecting fault.

(4)Data Storage Output Function

Units stored data in ECM are ROM and RAM, stored program in memorizer ROM is based on accurate calculation and a large

number of experiment data; the program compares and calculates to collected sensor signals constantly to control engine.

There is a special diagnosis connector in vehicle electrical control system, as long as connect vehicle ECM decomplier to the

diagnosis connector, you can visit vehicle ECM storage unit, and read stored fault code.

Besides, fault self-diagnosis system can output stream reflecting working condition of vehicle electrical control system by

diagnosis connector.

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Engine Electronic Component Structure Principle

Electronic components of electrical system mainly include sensor, actuator and ECM.

Generally, there are 3 wires, namely power supply, signal, grounding in sensor basic circuit. Some sensors don’t need power

supply, or place power supply circuit in ECM, therefore there are only signal and grounding two wires; if applies outer housing

grounding, it may have only one signal wire connected to ECM, thus make circuit very simple, but some sensor circuits are very

complicate. Complicate range of sensor circuit depends on sensor type and structure principle; sensors of engine electrical control

system mainly have switch type, resistance type, impulse type, voltage type.

Switch type sensor is a sensor of simplest structure, generally has two connected pins; its circuit has two kinds, namely grounding

type and power supply type, in which one pin of grounding type circuit is grounding, one pin of power supply type circuit is connected

to power supply.

Resistance type sensor is most used sensor in electrical control system, its structure has variable resistance type, potentiometer

type; generally uses principle of direct current circuit distributing voltage to produce electronic signal; to ensure accuracy of signal,

ECM supplies constant reference voltage as its working voltage (generally is 5V).

Variable resistance type sensor generally has 2 connecting pins, generally uses grounding type circuit, which one pin is signal, the

other pin is grounding; Potentiometer type sensor generally has 3 pins, namely power supply pin, signal pin and grounding pin. Impulse

type sensor has all kinds of principles and structure types, such as electromagnetic type using electromagnetic induce principle,

photoelectricity type using photoelectricity principle, Hoare type using Hall effect, magnetic resistance using magnetic resistance

principle, and its circuit are fairly complicate.

Voltage type sensor generally transforms change of detected parameter using electrochemistry principle, piezoelectricity effect

to change of voltage. Most voltage-type sensors don’t need working power supply.

Actuators of electrical control system mainly have electromagnetic valve, electrical power motor, relay, triode switch circuit and

indicating light. Actuator circuit usually is simple, generally has power supply and grounding two wires. ECM controls most actuators

by grounding method, power supplies of these actuators come from battery, grounding wires connect to ECM.

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Pin No.

Function

Power supply

5V power supply voltage signal

Pressure signal

Manifold pressure sensor signal

Grounding

Power supply grounding

Temperature signal

Intake temperature sensor signal

Engine Electronic Component Structure Instruction

Intake Temperature Pressure Sensor

1. Component Instruction

1). MT22.1 electrical control fuel injection system applies speed density air metric method, detects air amount getting into engine,

thus controls fuel injection pulse width, and accurately controls engine power output. Sensors are consist of intake absolute

pressure sensor and intake temperature sensor.

2). Intake absolute pressure sensor (MAP) is a pressure sensitive variable resistor. Pressure diaphragm in intake pressure sensor

connects to one magnet core in coil, when intake pressure in intake pipe changes, diaphragm drive magnet core to move, at

this time output voltage of sensor changes, ECM calculates engine intake amount according to output voltage of sensor, and

engine bases on the signal, refer to other signal, controls fuel injection amount of engine. MAP sensor is also used to measure

atmosphere pressure when starting, and in some condition permit ECM automatically adjusts in different altitude height. ECM

supplies MAP sensor 5V voltage, and receives voltage through signal line. Sensor supplies one line to grounding by its variable

resistor. Input signal of MAP sensor affects ECM control of fuel output and ignition timing.

3). Intake temperature sensor is a negative temperature coefficient (NTC) thermal resistor, resistance value decreases along with

intake temperature increasing, a comparison circuit in engine ECM monitors change of intake temperature.

2. Component installation position

Installed in intake manifold.

3. Component Circuit Diagram

Item

Standard value

Working voltage

5±0.1V

Working pressure range

10kPa

～ 115kPa

Working temperature range -40

～ 125 ℃

Power supply

Pressure signal

Temperature signal

Grounding

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Coolant Temperature Sensor

1. Component Instruction

Engine coolant temperature sensor detects engine coolant temperature, and transmits signal to ECM to control ignition timing and

fuel injection pulse width when starting, idling and normal running, and supply coolant temperature signal to meter to display coolant

temperature in meter. It uses a negative temperature coefficient thermal resistor, resistance value of thermal resistor decreases along

with temperature increases. ECM judges coolant temperature by output voltage of sensor, and supply mixture gas of optimum air-fuel

ratio.

2. Installation Position

Installed in side of cylinder head.

3. Component Circuit Diagram

Instruction: This vehicle is equipped with three-line-type coolant
temperature sensor.

Pin

Function

Pin A:

Output coolant temperature signal

Pin C:

Grounding

Pin B

Connect to coolant temperature gauge

Temperature

Standard resistance (Ω)

-10

16120

25

2795

85

283

115

115.7

A

B

C

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Pin No.

Function

A

5V power supply

B

Throttle valve motor
control(+)

C

Throttle valve motor
control(+)

D

TPS1 signal

E

TPS2 signal

F

Grounding

Electronic Throttle Valve

1. Component Instruction

Electronic control throttle valve assembly is one of the main parts of intake control management system in current engine

management system. It directly controls intake amount of engine, thus control engine speed and output power.

Electronic control throttle valve cancels machinery control mechanism of mechanism control type throttle valve, adds drive

motor, drive gear wheel mechanism, necessary transmission component and special throttle valve position sensor with more

stronger function and reliability.

As one of safety guarantee of system, system setting has dual output throttle valve position sensor, one throttle valve position

sensor increases along with opening degree of throttle valve, but output signal of the other throttle valve position sensor decreases

along with opening degree of throttle valve.

2. Installation position

Installed in intake manifold.

3. Component Circuit Diagram

Item

Standard value

Measured range of
throttle valve position
sensor

When in idling condition:
TPS1 is 6%

～ 14%; TPS2 is

86%

～ 94%.

When in totally open condition:
TPS1 is 86%

～ 94%.

Throttle valve
response time

Totally open to totally closed:
≤ 100ms
Totally closed to totally open:
≤ 150ms

A

B

C

D E F