Page 537 - Foton Workshop Manual - Tunland (AT)

DIAGNOSTICS - ENGINE CONTROL SYSTEM 04-391

No> Refer to the engine phenomenon diagnostic list - Idle troubleshooting to confirm
that the problem no longer exists.

4 . 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
04
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.
(e) Ignition switch: ON, read the data flow of the intake manifold absolute pressure
temperature sensor, intake mass flow sensor and the coolant temperature sensor
shown on the diagnostic tool.

Is the inspection result normal?
YES>To step 5.
No >Clean and change the default parts.

5 . Check the Check the position of the throttle
(a) Use a diagnostic tool to check whether the throttle is normal or not.
(b) Check whether the throttle opening changes normally or not, when steps the accelerator
pedal.
Is the inspection result normal?

YES>To step 6.
No >Repair and replace the default parts.

6 . Check the fuel injector
(a) Unplug the injector connector.
(b) Remove the fuel distribution pipes and injector outside the engine together.
(c) Add the battery voltage of 12 V directly to the injector.
(d) Every injector shall inject the fuel according to the standard flow and have uniform
atomization.

NOTICE

When check the injection status of the injectors, the fuel amount the four cylinder
injectors spraying differs largely in the same conditions, then it should change the
injector. Check whether the injector nozzle has colloidal substances or not, if it has,
it may use cleaning agent to soak and spray, or it may cause the insufficient of fuel
or bad acceleration etc.

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