Daewoo MATIZ Service Manual page 398

1F – 300 ENGINE CONTROLS
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.
Step
Were the Important Preliminary Checks performed?
1
1. Run the engine until it reaches operating
temperature.
2
2. Perform an emission test.
Did the vehicle pass the emission test?
1. Connect the scan tool to the Data Link Connector
(DLC).
2. Road test the vehicle.
3
3. Monitor the long term fuel trim memory.
Is the long term fuel trim memory within the value
specified?
Is the long term fuel trim memory below the value
specified?
4
Is the long term fuel trim memory above the value
specified?
5
1. Check for a properly installed fuel cap.
2. Check the fuel system pressure.
6
3. Perform an injector diagnosis.
Is the problem found?
1. Repair or replace any fuel system components as
needed.
7
2. Perform an emission test.
Did the vehicle pass the emission test?
1. Check the ignition system for proper operation.
2. Inspect the spark plugs for excessive wear,
insulation cracks, improper gap, or heavy
deposits.
8
3. Check the ignition wires for cracking, hardness, or
improper connections.
Is the problem found?
1. Repair or replace any ignition system components
as needed.
9
2. Perform an emission test.
Did the vehicle pass the emission test?
Action Value(s) Yes
–
Go to Step 2
–
System OK
–20 – 25 % Go to Step 6
Go to
"Diagnostic Aids
–20 % for DTC P0172"
Go to
"Diagnostic Aids
25 % for DTC P0171"
–
Go to Step 7
–
System OK
–
Go to Step 9
–
System OK
No
Go to
"Important
Preliminary
Checks"
Go to Step 3
Go to Step 4
Go to Step 5
–
Go to Step 8
–
Go to Step 10
–
DAEWOO M-150 BL2