Lifan 620. Manual — part 20

12. Ineffective acceleration or flameout

Table 1-62

S/N Operation Test

Results

Actions

Yes

Remove the trouble

1

Turn the ignition switch to ON. Check if there is

trouble information records with a diagnostic

instrument.

No Next

step

Yes Next

step

2

Check the air filter for smoothness.

3

4

5

6

7

8

9

No 15

Yes Next

step

10

Check if the fuel pressure is lower than 250kPa.

No 14

Yes Next

step

11

Close the fuel gauge valve. Turn on the ignition switch

again and keep the fuel pump working for 3 seconds.

Check if fuel pressure can be produced.

No 13

81

Table 1-62 (Continued)

S/N Operation Test

Results

Actions

Yes

Replace fuel pressure

regulator

12

Turn on the fuel gauge valve, and block the fuel return

pipe. Check if the fuel pressure is quickly produced.

No

Repair or replace fuel

injector or fuel pipe

Yes

Repair or replace fuel intake

pipe

13

Check the fuel intake pipe for leakage or blockage.

14

15

16

1

2

Yes Next

step

3

Run the engine at an idle speed. Check if the rotation

speed is normal.

No

Check and repair as per idle

speed trouble items

Yes Next

step

4

Run the engine at an idle speed. Check if the intake

air pressure is between 35kPa and 65kPa.

No

Check and repair

82

Table 1-63 (Continued)

S/N Operation Test

Results

Actions

Yes Next

step

5

Turn the ignition switch to ON. Connect an adapter

between the ECU and the harness. Check the voltage

of the pin J1-24 (signal output end of the throttle

position sensor), J1-05 (grounding end), J1-20 (as the

power supply for 4.5-5V sensor). Is it OK?

No

Repair or replace harness

Yes Next

step

6

Run the engine at an idle speed. Check if the ignition

advance angle is normal after the coolant reaches

7

8

9

10

11

12

13

Yes

Repair or replace fuel intake

pipe

14

Check the fuel intake pipe for leakage or blockage.

No

Replace fuel pump

Yes

Repair or replace fuel return

pipe

15

Check if the fuel return pipe is blocked or bent.

No

Replace pressure regulator

Yes

Replace or clean up

16

Check if the exhaust system is blocked.

No Replace

ECU

83

14. Poor acceleration

Table 1-64

S/N Operation Test

Results

Actions

Yes Repair

1

Check the clutch, tyre pressure, brake, tyre size and

four-wheel alignment for normal operation.

No Next

step

Yes Next

step

2

Check if the throttle can be fully opened.

3

4

5

6

7

8

fuel injector for normal operation.

No Next

step

Yes Next

step

9

Wash the fuel injector and check the fuel injector

again for normal operation.

No

Replace fuel injector

Yes Replace

fuel

10

Chek if the fuel is wrong or contains water.

No 16

84