Chery Fora (Elara A520). Manual - part 155

CHERY·A21 SERVICE MANUAL ENGINE EFI SYSTEM

7. Regular starts but the idle speed is not steady during engine heating.

General failure component: 1), water in fuel; 2), coolant temperature sensor; 3), spark
plug; 4), throttle valve and idle speed by pass port; 5), air intake port; 6), idle speed
regulator; 7), engine mechanical.

General diagnosis flow:

No.

Operating steps

Result

Follow up steps

Yes

Repair the air
intake system

Check the air cleaner if it is jammed; check the air

intake port if it is leaking.

Next step

Yes

Next step

Check spark plugs in every cylinder and observe its

type and clearance if it is accord with the regulation.

Adjust or replace

Yes

Cleaning the

related parts

Disassemble the idle speed regulator and check the
throttle valve and idle speed by pass port if there is

carbon deposition

Next step

Yes

Repair the line or

replace sensor

Pull off coolant temperature sensor joint and start the

engine; observe the engine if it is idle speed unsteady

during warming up the engine.

Next step

Yes

Replace part

Disassemble the injector, check the injector using the

injector special cleaning analysis meter and observe

if it is leaking or jammed or overflowing.

Next step

Yes

Change fuel

Check fuel conditions and check if the failure is

appeared after the fuel refilling

Next step

Yes

Trouble shoot

Check pressure conditions of every cylinder and

observe if there is big pressure difference between

the cylinders.

Next step

Yes

Diagnosis help

Connect EFI system adaptor, turn on the ignition

switch; check the power supply of pin No.12, 13, 44,

45 and No.63 if it is in right conditions; check pin

armature of No.3, 51, 53, 61 and No.80 if it is in

right conditions.

Repair the

corresponding

line

CHERY·A21 SERVICE MANUAL ENGINE EFI SYSTEM

8. Regular starts but idle speed is not steady after the engine heating.

General failure component: 1), water in fuel; 2), coolant temperature sensor; 3), spark
plug; 4),throttle valve and idle by pass port; 5), air intake port; 6), idle speed regulator;
7), engine mechanical part.

General diagnosis flow:

No.

Operating steps

Result Follow up steps

Yes

Repair the air
intake system

Check the air cleaner if it is jammed; check the air intake

port if it is leaking.

Next step

Yes

Next step

Check spark plugs in every cylinder and observe its type

and clearance if it is accord with the regulation.

Adjust or

replace

Yes

Cleaning the

related parts

Disassemble the idle speed regulator and check the throttle

valve and idle speed by pass port if there is carbon

deposition

Next step

Yes

Repair the line

or replace

sensor

Pull off coolant temperature sensor joint and start the

engine; observe the engine if it is idle speed unsteady

during warming up the engine.

Next step

Yes

Replace part

Disassemble the injector, check the injector using the

injector special cleaning analysis meter and observe if it is

leaking or jammed or overflowing.

Next step

Yes

Change fuel

Check fuel conditions and check if the failure is appeared

just after the fuel refilling

Next step

Yes

Trouble shoot

Check pressure conditions of every cylinder and observe if

there is big pressure difference between the cylinders.

Next step

Yes

Diagnosis help

Connect EFI system adaptor, turn on the ignition switch;

check the power supply of pin No.12, 13, 44, 45 and No.63

if it is in right conditions; check pin armature of No.3, 51,

53, 61 and No.80 if it is in right conditions.

Repair the

corresponding

line

CHERY·A21 SERVICE MANUAL ENGINE EFI SYSTEM

9. Regular starts but idle speed is not steady or dying out when there is partial loading.

General failure component: 1) air conditioner system; 2) idle speed regulator; 3)
injector.

General diagnosis flow:

No.

Operating steps

Result

Follow up steps

Yes

Cleaning the

related parts

Disassemble the idle speed regulator and check the
throttle valve and idle speed by pass port if there is

carbon deposition.

Next step

Yes

To step No.4

Observe if the engine output power increased when

the air conditioner is switched on, that is using EFI
system diagnosis meter observing ignition angle of

advance, fuel injection pulse width and changes of air

intake flow.

Next step

Yes

Next step

Connect EFI system adaptor; break connecting line of

ECU pin No.75; check the cable end if it is up level

signal when the air conditioner is switched on.

Repair air

conditioning

system

Yes

Next step

Check air conditioning system pressure; check the

compressor solenoid clutch and air conditioner

compressor pump fuel conditions and check if it is

working correctly.

Repair the air

conditioning sys.

Yes

Replace fault part

Disassemble the injector, check the injector using the

injector special cleaning analysis meter and observe if

it is leaking or jammed or overflowing.

Next step

Yes

Diagnosis help

Connect EFI system adaptor, turn on the ignition

switch; check the power supply of pin No.12, 13, 44,

45 and No.63 if it is in right conditions; check pin

armature of No.3, 51, 53, 61 and No.80 if it is in right

conditions.

Repair the

corresponding

line

CHERY·A21 SERVICE MANUAL ENGINE EFI SYSTEM

10. Regular starts with high idle speed.

General failure component: 1) throttle valve and idle speed by pass port; 2) vacuum
pipe; 3) idle speed regulator; 4) coolant temperature sensor; 5) ignition timing.

General diagnosis flow:

No.

Operating steps

Result Follow up steps

Yes

Adjust

Check accelerator cable if it is blocked or over tightening

Next step

Yes

Repair the air

in taking

system

Check the air intake system and its connecting vacuum pipe

if it is leaking.

Next step

Yes

Clean related

part

Disassemble the idle speed regulator and check the throttle

valve and idle speed by pass port if there is carbon

deposition

Next step

Yes

Repair line or

replace sensor

Take off the coolant temperature sensor joint; start the

engine and observe if it has high idle speed.

Next step

Yes

Next step

Check the engine ignition timing if it is accord with the

regulations.

Repair the

ignition timing

Yes

Diagnosis help

Connect EFI system adaptor, turn on the ignition switch;

check the power supply of pin No.12, 13, 44, 45 and No.63

if it is in right conditions; check pin armature of No.3, 51,

53, 61 and No.80 if it is in right conditions.

Repair the

corresponding

line

Content .. 153 154 155 156 ..