Daewoo CIELO EURO III Manual page 366

1F – 197 ENGINE CONTROLS
Step
1. Turn the ignition switch OFF and inspect the
throttle body, throttle plate and Idle Air Control
(IAC) passages for choking and foreign objects.
8
2. Repair as necessary.
Does the inspection reveal a condition requiring a
repair?
Start the engine with the vehicle in park or neutral
and the A/C OFF and note the idle quality.
9
Is a low or unsteady idle being experienced?
Idle the engine.
10
Are the IAC counts below the specified value?
1. Disconnect the MAP sensor.
2. Operate the vehicle while in Closed Loop.
11
Does the Fuel Trim Index increase above the speci-
fied value?
1. Check the IAC valve performance. Refer to "DTC
P0506 Idle Speed RPM Lower Than Desired Idle
Speed" or "DTC P0507 Idle Speed RPM Higher
Than Desired Idle Speed" in this section
12
2. Repair as necessary.
Does the inspection reveal a condition requiring a
repair?
1. Disconnect the vacuum hose from the fuel
pressure regulator and inspect the hose for the
presence of fuel.
2. If fuel is present in the vacuum hose, replace the
13
fuel pressure regulator.
Does the fuel pressure regulator require replace-
ment?
1. Turn the ignition switch ON, with the engine OFF.
2. Slowly depress the accelerator pedal.
Does the Throttle Position (TP) display increase
14
steadily and evenly from its minimum voltage at
closed throttle to its maximum voltage at wide–open
throttle (WOT)?
1. Perform the Fuel System Diagnosis.
2. If the table isolates a problem, repair as
15
necessary.
Does the table isolate a problem requiring a repair?
1. Perform the Evaporative (EVAP) Emission
Control System Diagnosis.
2. If the table isolates a problem, repair as
16
necessary.
Is a problem isolated that requires a repair?
1. Perform the Fuel Injector Balance Test.
2. If the table isolates a problem, repair as
17
necessary.
Does the table isolate a problem requiring a repair?
DTC P0172 Fuel Trim System Too Rich (Cont'd)
Action Value Yes
–
Go to Step 21
–
Go to Step 10
100 Go to Step 12
–20% Go to Step 20
–
Go to Step 21
–
Go to Step 21
–
Go to Step 15
–
Go to Step 21
–
Go to Step 21
–
Go to Step 21
No
Go to Step 9
Go to Step 12
Go to Step 11
Go to Step 12
Go to Step 13
Go to Step 14
Go to Step 19
Go to Step 16
Go to Step 17
Go to Step 18
DAEWOO T-154 BL2,3