Page 527 - Foton Workshop Manual - Tunland (AT)

DIAGNOSTICS - ENGINE CONTROL SYSTEM 04-381

3 . Check the intake system
(a) Check whether it leaks of the engine intake systems or not.
(b) Check whether the intake pipe has the leakage sound of "hissing " when runs.
(c) Check whether the intake tube is disconnected, cracked, deformed or sealing aged
or not.
04
Check whether the intake tube is disconnected, cracked or not. Is the inspection result
normal?
YES>To step 4.
No > Repair, change or assemble again.

4 . Check the relevant accessories
(a) Check whether the turbocharger system line is connected tightly or damaged or not.
(b) Whether the EGR system pipe is installed fixedly or damaged or not.
(c) Whether the positive crankcase ventilation hose is installed fixedly or damaged or not.
Is the inspection result normal?

YES>To step 5.
No > Modify or change.

5 . Check the throttle body
(a) Check whether the throttle has oil and carbon deposition is stuck or not, the air intake
channel around the throttle has oil and carbon deposition or not.
(b) Start the motor, idling rotation.
(c) Use a diagnostic tool, perform the throttle test.
(d) When the diagnostic tool controls the throttle rotation, the motor speed can have high
or low changes simultaneously.
(e) Unplug the idling motor plug inspection, measuring connector terminal should be 12V
voltages.
(f) When turn off the ignition switch, depress and release the accelerator pedal to check
the throttle rotates or not.

Is the inspection result normal?

YES>To step 6.
No > Clean, fix or change the harness, connector or throttle valve.

6 . Check the coolant temperature sensor, intake mass flow sensor and intake
manifold absolute pressure temperature sensor.
(a) Check the coolant temperature sensor, intake manifold absolute pressure temperature
sensor and intake mass flow sensor are installed correctly.
(b) Remove the coolant temperature sensor, intake manifold absolute pressure temperature
sensor and intake mass flow sensor.
(c) Check whether the sensing hole is blocked or not, and whether the resistance between
the terminals is in line with the standard or not.
(d) Check the coolant temperature sensor , intake mass flow sensor and intake manifold
absolute pressure temperature sensor are dirty.

Page 527