Daewoo Nubira User Manual page 569

1F – 366IENGINE CONTROLS
Step
7
1. Check the ignition system output with a spark
tester.
2. Inspect the spark plugs for the proper heat
range and gap.
3. Check for the proper operation of the ignition
controls.
Is the ignition system operating properly?
8 Repair or replace the ignition system components as
needed.
Is the repair complete?
9
1. Connect the scan tool to the Data Link Con-
nector (DLC).
2. Road test the vehicle at the speed of the com-
plaint.
3. Monitor the long term fuel trim reading from the
scanner data stream.
Is the long term fuel trim reading above the value
specified?
10 Check the fuel system pressure.
Is the problem found?
11 Repair or replace the fuel system components as
needed.
Is the repair complete?
12
1. Inspect for carbon buildup inside the engine.
2. Remove the carbon with a top engine cleaner.
Follow the instructions supplied with the prod-
uct.
3. Check the basic engine parts such as the cam-
shaft, the cylinder head, the pistons, etc. for
excessive wear.
4. Replace any excessively worn parts.
Is the procedure complete?
13
1. Check the Exhaust Gas Recirculation (EGR)
valve for proper operation.
2. Check the air intake system for proper opera-
tion.
3. Check the Torque Converter Clutch (TCC) op-
eration and transaxle shift points.
4. Check the service bulletins for Programmable
Read–Only Memory (PROM) updates.
5. Check the cylinder compression.
6. Repair or replace any faulty components.
Are all checks and repairs complete?
Action Value(s) Yes
Go toStep 9
System OK
150 counts Go to"Diagnos-
tic Aids for
DTC P0171"
41–47 psi Go toStep 11
(284–325 kPa)
System OK
Go toStep 13
System OK
No
Go toStep 8
Go toStep 10
Go toStep 12
DAEWOO V–121 BL4