Daewoo Matiz (2003 year). Manual - part 98

1F – 302  ENGINE CONTROLS

DIESELING, RUN-ON

Definition: An engine continues to run after the ignition
switch is turned OFF.

Step

Action

Value(s)

Yes

No

1

Were the Important Preliminary Checks performed?

–

Go to Step 2

Go to

“Important

Preliminary

Checks”

2

Does the engine run smoothly after the ignition
switch is turned OFF?

–

Go to Step 3

Go to Step 4

3

1. Check the ignition switch and the ignition switch

adjustment.

2. Replace the ignition switch if needed.
Is the repair complete?

–

System OK

–

4

1. Check the evaporative emission system.
2. Check for leaking fuel injectors.
3. Check the Idle Air Control (IAC) valve operation.
4. Inspect for vacuum leaks.
5. Check for the proper base idle setting.
Are all checks and repairs complete?

–

System OK

–

ENGINE CONTROLS  1F – 303

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.

Step

Action

Value(s)

Yes

No

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 3

Go 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 5

Go 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 7

Go to Step 8

7

Repair 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

–

1F – 304  ENGINE CONTROLS

REPAIR INSTRUCTIONS

ON-VEHICLE SERVICE

D102F502

D102F501

FUEL PUMP

Tools Required

DW 140–010A Fuel Pump Lock Ring Remover/Installer.

Removal Procedure

Caution: The fuel system is under pressure. To
avoid fuel spillage and the risk of personal injury or
fire, it is necessary to relieve the fuel system pres-
sure before disconnecting the fuel lines.

1. Relieve the fuel system pressure.

D

Start the engine and remove the rear seat cushon
(1).

D

Remove the fuel pump access cover (2).

D

Disconnect the fuel pump assembly electrical con-
nector lock pin (3).

D

Disconnect the fuel pump assembly electrical con-
nector (4).

D

Crank the engine for an additional 10 seconds.

D102F503

2. Disconnect the fuel lines from the fuel pump.

D

Disconnect the fuel outlet line (1).

D

Disconnect the fuel tank return line (2).

ENGINE CONTROLS  1F – 305

D12F504A

3. Remove the fuel pump assembly from the tank.

D

Install the fuel pump lock ring remover/installer DW
140– 010A.

D

Turn the fuel tank lock ring counterclockwise (1).

D102F505

D

Remove the fuel pump assembly (2).

D

Remove the fuel pump gasket (3).

D102F506

Installation Procedure

1. Install in the reverse order of removal.

2. Perform an operational check of the fuel pump.

D

Perform an operational check of the ignition switch
ON the 2 seconds fuel pump operation.

D102F507

FUEL PRESSURE REGULATOR

Removal Procedure

Caution: The fuel system is under pressure. To
avoid fuel spillage and the risk of personal injury or
fire, it is necessary to relieve the fuel system pres-
sure before disconnecting the fuel lines.

1. Relieve the fuel system pressure after remove the

fuel pump assembly. Refer to “Fuel Pump”  in this
section.