Engine Electrical System

6) Unstable idle speed at all time
Yes
Fix the indicated
malfunction
1
Turn the ignition switch to “ON”
position. Inspect with the diagnostic
tester to see whether there is any
malfunction information record.
No Proceed to next step.
Yes
Repair or replace idle
speed actuator
2
Verify that the EWD3 idle speed actuator
or idle speed actuator with step motor is
jammed.
No Proceed to next step.
Yes
Inspect the wiring
harness and plug in
connector
3
Connect the ignition switch and verify
that the links between water temperature
sensor, idle speed step motor and ECU
are properly connected.
No Proceed to next step.
Yes Proceed to Step 8
4
Run the engine at idle speed and cut off
the cylinders one by one in order to
observe whether the speed is decreasing
or fluctuating.
No Proceed to next step.
Yes Proceed to next step.
5
Verify that the fuel injector of each
cylinder functions normally.
No
Inspect the fuel injector
and the wiring harness
Yes Proceed to next step.
6
Verify that the resistance of each cylinder
high voltage cable is normal.
No Replace
Yes Replace
7 Verify that the ignition coil is damaged.
No Proceed to next step.
Yes Proceed to next step.
8 Verify that the spark plug is normal.
No Replace the spark plug
Yes Proceed to next step.
9
Connect the fuel manometer valve. Short
the 30# and 87# pins of the fuel pump
relay to operate the fuel pump in order to
verify that the fuel pressure is being
maintained at about 350kPa.
No Proceed to Step 13.
Yes Proceed to Step 12.
10
Provide a voltage supply of 12V with
special connector between the battery and
the fuel injector, and verify that the fuel
injector functions normally.
No Proceed to next step.
Yes Proceed to next step.
11
After washing and cleaning the fuel
injector, verify again that it can function
normally.
No Replace the fuel injector
Yes Replace the fuel
12
Verify that the fuel is deteriorated or
contaminated with water.
No Proceed to Step 18
Yes Proceed to next step.
13
Verify that the fuel pressure is lower than
350kPa.
No Proceed to Step 17.
14 Close the fuel manometer valve. Connect Yes Proceed to next step.
E-72
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