Chery SQR 7160 sedan. Manual - part 121

 

4.2 Hard to start 

Check fault 

codes 

 

Determine fault source upon fault 

codes 

   

Check if air intake system 

vacuum leakage or intake 

valve dirt 

 

1 Hose connection 

2 throttle valve body air intake 

valve 

3 PCV hose 

 

check if ignition system fault   

1 wire 

2 ignition coil 

3 spark 

 

1 Remove fuel injector 

connector on each cylinder 

2 keep the spark plug about 8mm 

away from cylinder body. Start 

motor and watch firing. A strong 

fire should be visible 

 

Watching firing of each cylinder and check spark and spark plug gap   

Spark plug gap: 1mm   

Note: If necessary, measure compression pressure and air valve gap 

 

1 fuel injector leakage or short 

2 fuel injector wire short   

3 over fuel injection 

 

Check fuel supply: 

1 if fuel tank is empty 

2 fuel supply pipe fuel pressure. When ignition key is 

turned to ON position, the pump should operate 1~2 

seconds. 

Listening pump operating sound in fuel tank; 

Feeling pressure in fuel return pipe.   

 

1 fuel circuit leakage or 

deformation 

2 fuse 

3 pump relay 

4 fuel pump 

5 fuel pump filter 

6 fuel pressure 

regulator 

7 fuel injector 

 

Check idle step motor 

1 idle motor mount screw 

2 when ignition is turned on, short 

vibration should be felt. 

 

1 replace or turn mount 

screw 

2 step motor connection 

3 step motor 

 

Check circuit   

Using voltmeter or 

oscilloscope 

 1circuit 

connection 

2 ECU voltage 

Fusible link 

Fuse  

 

4.3 Rough Idle 

 

Check fault code 

 

determine fault source upon fault 

code 

 

 

Check air intake system 

vacuum leakage, air intake 

valve dirt 

1 Hose connection 

2 throttle valve body air intake 

valve  

3 intake manifold mounting 

 

Check air filter core 

Wash or replace 

 

Check ignition system fault 

1 check if wire power leakage 

2 check if ignition coil breakage 

or damage 

1 check high-tension 

wire  

2 check ignition coil 

 

Watch firing of each 

cylinder and check spark 

plug and spark plug gap 

Plug gap: 8mm   

NOTE: if necessary, 

check compression 

pressure and air valve 

gap 

1 replace spark plug 

2 cylinder compression 

pressure 

3 air valve gap 

 

Throttle valve position 

sensor and connection, 

repair or replace as 

necessary 

Check throttle valve position 

sensor 

 

Check step motor fault 

1 check mounting 

screw 

2 short vibration 

should be felt when 

ignition turned on 

1 measure step motor coil 

resistance 

2 check step motor wire 

3 replace or turn idle motor 

mounting screw 

 

 

Check fuel circuit fuel 

pressure 

 

1 check fuel pressure regulator 

2 check fuel pump 

3 check fuel filter, repair or replace as 

necessary 

 

 

Check fuel injector 

 

Check fuel injector, injector 

dirt, and repair or replace as 

necessary. 

 

Check coolant temperature 

sensor 

Check coolant temperature 

sensor and connector, repair or 

replace as necessary 

 

   

Check intake air 

temperature  pressure 

sensor 

 

Check intake air temperature 

pressure sensor 

 

Check oxygen sensor 

 

Check oxygen sensor, And 

replace if damaged. 

 4.4  High Idle Speed   

 

Check fault 

codes 

 

  Determine fault sources 

upon diagnostic codes. 

 

Check air intake 

system 

Vacuum leakage 

 

1 hose connection 

2 throttle valve body 

intake air valve 

3 intake manifold 

installation 

 

Check throttle 

position sensor 

 

Throttle position sensor 

and connection, repair and 

replace when necessary.   

 

Check step 

motor fault 

 

1 check step motor coil 

resistance 

2 when warming up and 

engine idle, use scan tester 

to read step motor total 

steps, and adjust the idle 

screw till total steps is 

20-40  

 

Check coolant 

temperature 

sensor 

 

Check coolant temperature 

sensor and connecting 

wire,  repair or replace as 

necessary. 

 

 

Check fuel 

pressure 

 

Check pressure regulator, 

and fuel pressurea, repair 

or replace as necessary. 

 

Check fuel 

injector 

 

fuel injector, repair or 

replace as necessary. 

 

4.5 Low idle speed   

If engine idle speed is low referring to each actuator and sensor mentioned above, check 

following components: 

Engine  coolant temperature sensor fault: check engine coolant temperature sensor and 

wire, repair or replace as necessary. 

Air intake    temperature sensor fault: check air intake temperature sensor and wire,repair or 

replace as necessary.   

Step motor fault or stuck 

Throttle position sensor fault: check engine throttle position sensor and wire, repair or 

replace when necessary. 

Fuel pressure and injector