Page 586 - Foton Workshop Manual - Tunland (AT)

04-440 DIAGNOSTICS - ENGINE CONTROL SYSTEM

THE ENGINE RUNS ROUGH OR MISFIRING

Fault phenomenon Diagnosis logic Possible reasons
• Poor fuel quality
• Turbocharger fault
• Fuel • Injector fault
04
• Turbocharger • Leakage in the intake
• High pressure oil pump system
• Fuel pipe • Low fuel pressure
• Fuel system • Air filter blocked
• Cylinder compression • High pressure oil pump
The engine runs rough or pressure blocked
misfiring • Injection timing • Incorrect injection timing
• Intake heater • Intake heater fault
• Intake system • Too low of the cylinder
• Exhaust system compression pressure
• EGR system • Exhaust system blocked
• Coolant temperature sensor • EGR system fault
• ECM • Coolant temperature sensor
fault
• ECM fault

Diagnosis Procedure

1 . Check the engine data
(a) Ignition switch: OFF.
(b) Connect the diagnosis tool with the fault diagnosis connector (16 pins) on the lower
left of the dashboard.
(c) Ignition switch: ON, and start the diagnostic tool.
(d) Read the motor data shown on the diagnostic tool.

Check whether the data flow is normal or not.

YES>To step 2.
No >Maintenance related faults.

2 . Check the intake system
(a) Check whether air filter is blocked.
(b) Check whether pipe of the intake system leaks.
(c) Check whether turbocharger can work properly.

Is the inspection result normal?
YES>To step 3.

No >Maintenance related faults.

3 . Check intake heater and its circuit
(a) Check whether the intake heater is damaged or not.
(b) Check whether the intake heater circuit is normal or not.

Page 586