spark plugs replace DAEWOO MATIZ 2003 Service User Guide

1F–298 ENGINE CONTROLS
DAEWOO M-150 BL2
Rough, Unstable, or Incorrect Idle, Stalling (Cont’d)
StepActionValue(s)YesNo
12
Is the long term fuel trim reading below the value
specified?
–20%
Go to
“Diagnostic Aids
for DTC P0172”
Go to Step 13
13
Is the long term fuel trim reading above the value
specified?
25%
Go to
“Diagnostic Aids
for DTC P0171”
–
14
1. Disconnect all of the fuel injector harness
connectors at the fuel injectors.
2. Connect an injector test light between the
harness terminals of each fuel injector connector.
3. Note the test light while cranking the engine.
Does the test light blink for all of the fuel injectors?
–
Go to Step 16Go to Step 15
15
1. Repair or replace the faulty injector drive circuit
harness, the connector, or the connector
terminals as needed.
2. If the harness, the connectors, and the terminals
are OK, replace the Engine Control Module
(ECM).
Is the repair complete?
–
System OK
–
16
Measure the resistance of each of the fuel injectors.
Is the resistance within the value specified (the
resistance will increase slightly at higher
temperatures)?
11.6–12.4 ΩGo to Step 18Go to Step 17
17
Replace any fuel injectors with a resistance that is
out of specifications.
Is the repair complete?
–
System OK
–
18Perform an injector diagnosis.
Is the problem found?–Go to Step 19Go to Step 20
19Replace any leaking or restricted fuel injectors.
Is the repair complete?–System OK–
20
1. With the engine OFF, disconnect the fuel
pressure regulator vacuum hose.
2. Thoroughly inspect the fuel pressure regulator
vacuum port and the fuel pressure regulator
vacuum hose for the presence of fuel.
Is the problem found?
–
Go to Step 21Go to Step 22
21Replace the fuel pressure regulator as needed.
Is the repair complete?–System OK–
22
1. Check the ignition system output voltage for all of
the cylinders using a spark tester.
2. Inspect the spark plugs for excessive wear,
insulation cracks, improper gap, or heavy
deposits.
3. Inspect the ignition wires for cracking, hardness,
or improper connections.
4. Replace any ignition wires with a resistance over
the value specified.
Is the problem found?
30000 ΩGo to Step 23Go to Step 24
23
Repair or replace any ignition system components
as needed.
Is the repair complete?
–
System OK
–

1F–300 ENGINE CONTROLS
DAEWOO M-150 BL2
EXCESSIVE EXHAUST EMISSIONS OR ODORS
Definition: A vehicle fails an emission test. The vehicle
has an excessive rotten egg smell. Excessive odors do
not necessarily indicate excessive emissions.
StepActionValue(s)YesNo
1
Were the Important Preliminary Checks performed?
–
Go to Step 2
Go to
“Important
Preliminary
Checks”
2
1. Run the engine until it reaches operating
temperature.
2. Perform an emission test.
Did the vehicle pass the emission test?
–
System OKGo to Step 3
3
1. Connect the scan tool to the Data Link Connector
(DLC).
2. Road test the vehicle.
3. Monitor the long term fuel trim memory.
Is the long term fuel trim memory within the value
specified?
–20 – 25 %Go to Step 6Go to Step 4
4
Is the long term fuel trim memory below the value
specified?
–20 %
Go to
“Diagnostic Aids
for DTC P0172”
Go to Step 5
5
Is the long term fuel trim memory above the value
specified?
25 %
Go to
“Diagnostic Aids
for DTC P0171”
–
6
1. Check for a properly installed fuel cap.
2. Check the fuel system pressure.
3. Perform an injector diagnosis.
Is the problem found?
–
Go to Step 7Go to Step 8
7
1. Repair or replace any fuel system components as
needed.
2. Perform an emission test.
Did the vehicle pass the emission test?
–
System OK
–
8
1. Check the ignition system for proper operation.
2. Inspect the spark plugs for excessive wear,
insulation cracks, improper gap, or heavy
deposits.
3. Check the ignition wires for cracking, hardness, or
improper connections.
Is the problem found?
–
Go to Step 9Go to Step 10
9
1. Repair or replace any ignition system components
as needed.
2. Perform an emission test.
Did the vehicle pass the emission test?
–
System OK
–

ENGINE CONTROLS 1F–303
DAEWOO M-150 BL2
BACKFIRE
Definition: Fuel ignites in the intake manifold, or in the
exhaust system, making a loud popping noise.Important: Before diagnosing the symptom, check ser-
vice bulletins for updates.
StepActionValue(s)YesNo
1
Were the Important Preliminary Checks performed?
–
Go to Step 2
Go to
“Important
Preliminary
Checks”
2
1. Inspect for crossed or crossfiring ignition wires.
2. Check the ignition system output voltage for all
cylinders using a spark tester.
3. Inspect the spark plugs for excessive wear,
burned electrodes, improper gap, or heavy
deposits.
Is the problem found?
–
Go to Step 3Go to Step 4
3
Repair or replace any ignition system components
as needed.
Is the repair complete?
–
System OK
–
4
1. Check the fuel system operation.
2. Check the fuel injectors by performing an injector
diagnosis.
Is the problem found?
–
Go to Step 5Go to Step 6
5
Repair or replace any fuel system components as
needed.
Is the repair complete?
–
System OK
–
6
1. Inspect the Electric Exhaust Gas Recirculation
(EEGR) gasket for a leak or a loose fit.
2. Check the EEGR valve for proper operation.
3. Inspect the intake manifold and the exhaust
manifold for a casting flash.
Is the problem found?
–
Go to Step 7Go to Step 8
7Repair or replace any components as needed.
Is the repair complete?–System OK–
8
1. Inspect the timing belt for proper installation and
tension.
2. Check the engine compression.
3. Inspect the intake manifold gasket and the
exhaust manifold gasket for leaks.
4. Check for sticking or leaking valves.
5. Repair or replace any components as needed.
Are all checks and corrections complete?
–
System OK
–