Chery QQ6 (S21) / S12LHD. Manual — part 198

Service Manual for Chery

QQ6

(UMC EFI for 473F Engine)

After Sales Service Department of Chery

Automobile Sales Co., Ltd.

CONTENTS

CHAPTER ONE DISASSEMBLY AND INSTALLATION OF ELECTRONIC FUEL

INJECTION SYSTEM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...4

I. Disassembly and Installation of Components of Electronic Fuel Injection System . . . . ..4

CHAPTER TWO PRINCIPLE OF ELECTRONIC FUEL INJECTION SYSTEM . . . . ...6

I. Overhaul of System Components . . . . . . . . . . . . . . . . . . . . . . . ..6

1. Intake Air Temperature Pressure Sensor . . . . . . . . . . . . . . . . . . ...6

2. Tachogenerator of Engine . . . . . . . . . . . . . . . . . . . . . . . . .8

3. Phase Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...10

4. Water Temperature Sensor . . . . . . . . . . . . . . . . . . . . . . . ..10

5. Knock Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..12

6. Electric Throttle Body. . . . . . . . . . . . . . . . . . . . . . . . . .12

7. Oxygen Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

8. Fuel Pump Assembly . . . . . . . . . . . . . . . . . . . . . . . . . ..16

9. Injector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

10. Ignition Coil . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..19

11. Spark Plug. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21

12. Carbon Canister Solenoid Valve Control . . . . . . . . . . . . . . . . . ..22

13. Electronic Accelerator Pedal. . . . . . . . . . . . . . . . . . . . . . .24

14. Three-way Catalytic Converter . . . . . . . . . . . . . . . . . . . . . .24

15. Fan Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...25

16. Position Sensor of Double Brake Pedal . . . . . . . . . . . . . . . . . . 26

17. Clutch Position Sensor . . . . . . . . . . . . . . . . . . . . . . . . ..26

18. A/C Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . ...27

CHAPTER TWO FUNDAMENTAL PRINCIPLE FOR FAILURE DIAGNOSIS OF

ELECTRONIC FUEL INJECTION SYSTEM . . . . . . . . . . . . . . . . . . . .28

1. Failure Information Records . . . . . . . . . . . . . . . . . . . . . . . . ...28

2. Failure State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

3. Failure Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..28

4. Failure Frequency Counter . . . . . . . . . . . . . . . . . . . . . . . . . .28

5. Limp Home . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29

6. Failure Alert. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

7. Readout of Failure . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..29

8. Clearing Failure Information Records . . . . . . . . . . . . . . . . . . . . . 30

9. Failure Locating. . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..30

10. Failure Code Table. . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

11. The Steps for Implementation of Failure Diagnosis According to Failure Information

Records . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...35

11.1 Electronic Throttle Failure . . . . . . . . . . . . . . . . . . . . . . ..35

11.2 Knock Sensor failure. . . . . . . . . . . . . . . . . . . . . . . . ...36

11.3 Air Pressure Sensor Failure . . . . . . . . . . . . . . . . . . . . . . 37

11.4 Front Oxygen Sensor Failure . . . . . . . . . . . . . . . . . . . . . ..38

11.5 Rear Oxygen Sensor Failure . . . . . . . . . . . . . . . . . . . . . ...40

11.6. Coolant Temperature Sensor Failure . . . . . . . . . . . . . . . . . . .42

11.7 Failure in Driver Stage of Injector . . . . . . . . . . . . . . . . . . . ..43

11.8 Failure in Driver Stage of Canister Control Valve. . . . . . . . . . . . . ..44

11.9 Failure in Driver Stage of Malfunction Indicator Lamp (MIL) . . . . . . . . ..45

11.10 Failure in Driver Stage of 1#, 2# Coils of Step Motor . . . . . . . . . . . ..46

11.11 Craftshaft Position Sensor Failure . . . . . . . . . . . . . . . . . . . 47

11.12 Craftshaft Position Sensor Failure . . . . . . . . . . . . . . . . . . . 48

11.12 Ignition Coil Failure. . . . . . . . . . . . . . . . . . . . . . . . ..49

11.13 Accelerator Pedal Position Sensor Failure. . . . . . . . . . . . . . . . 50

11.14 Double Brake Swtich . . . . . . . . . . . . . . . . . . . . . . . . 51

11.15 Theft-proof Control System Failure. . . . . . . . . . . . . . . . . . ..52

12. Steps for Implementation of Failure Diagnosis by Engine Symptom. . . . . . . . ...53

12.1 Perform Preliminary Inspection First before Following the Steps for Implementation

of Failure Diagnosis by Engine Symptom. . . . . . . . . . . . . . . . . . . .53

12.2 The Engine Does not Rotate or Rotates Slowly when Starting. . . . . . . . ...55

12.3 When Starting, Engine Can be Dragged to Rotate but Can not Start with Success. ...56

12.4 Warm Starting Difficulty . . . . . . . . . . . . . . . . . . . . . . . 58

12.5 Engine Speed is Normal, but it is Difficult to Start at any Time. . . . . . . . ...60

12.6 Cold Starting Difficulty . . . . . . . . . . . . . . . . . . . . . . . ..62

12.7 Unsteady Idle Speed at Any Time . . . . . . . . . . . . . . . . . . . ..64

12.8 Unsteady Idle Speed during Warming up Process . . . . . . . . . . . . . ..66

12.9. Unsteady Idle Speed after Warming up . . . . . . . . . . . . . . . . . .67

12.10 Unsteady Idle Speed or Extinguish with Load (A/C etc.). . . . . . . . . . .69

12.11 Periodic Unsteadiness (Have to Perform Self-study again after ECU is Power off) 70

12.12 Too High Idle Speed (Have to Perform Self-study again after ECU is Power off) ..72

12.13. Engine Revolution Speed is too Low or Flameout . . . . . . . . . . . . ..73

12.14 Slow Response when Accelerating . . . . . . . . . . . . . . . . . . ...75

12.15 Poor Performance and Disability when Accelerating. . . . . . . . . . . . ..77

12.16 Unable to Reach the Maximum Revolution when Accelerating. . . . . . . ...79

12.17 When Releasing Accelerator Pedal after Acceleration, Unsteady Idle Speed Occurs

at Instant, even Extinguishes. . . . . . . . . . . . . . . . . . . . . . . ...81

12.18 A/C System Failure. . . . . . . . . . . . . . . . . . . . . . . . ...83

13. Safety Precautions for System Maintenance. . . . . . . . . . . . . . . . . . .84

13.1 Safety Precautions for Diagnosis and Maintenance of Gasoline Injection Electronic

Control System . . . . . . . . . . . . . . . . . . . . . . . . . . . . ...84

Chapter One Disassembly and Installation of Electronic Fuel

Injection System

I. Disassembly and Installation of Components of Electronic Fuel

Injection System

1. Disassembly and installation of engine control unit (ECU).

2. Position and disassembly of intake air pressure sensor.

3. Position and disassembly of camshaft position sensor.

4. Remove fixing hoop of intake hose.