Daewoo Matiz (2003 year). Manual - part 94

1F – 286 ENGINE CONTROLS

SURGES OR CHUGGLES

Definition: Engine power variation under steady throttle
or cruise. Feels like the vehicle speeds up and slows
down with no change in the accelerator pedal position.

Important: Make sure the driver understands A/C com-
pressor operation as described in the owner’s manual.

The speedometer reading and the speed reading on the
scan tool should be equal.

Before diagnosing the symptom, check service bulletins
for updates.

Step

Action

Value(s)

Yes

Were the Important Preliminary Checks performed?

–

Go to Step 2

Go to

“Important

Preliminary

Checks”

Connect the scan tool to the Data Link Connector
(DLC).
Does the oxygen sensor (O2S) respond quickly to
different throttle positions?

–

Go to Step 4

Go to Step 3

1. Check the O2S for silicone or other contaminants

from fuel or use of improper Room Temperature
Vulcanizing (RTV) sealant.

2. Replace the contaminated O2S.
Is the repair complete?

–

System OK

–

1. Drive the vehicle at the speed of the complaint.
2. Monitor the long term fuel trim reading using the

scan tool.

Is the long term fuel trim reading within the value
specified?

–20–25%

Go to Step 7

Go to Step 5

Is the long term fuel trim reading below the value
specified?

–20%

Go to

“Diagnostic Aids

for DTC P0172”

Go to Step 6

Is the long term fuel trim reading above the value
specified?

25%

Go to

“Diagnostic Aids

for DTC P0171”

–

Check the fuel system pressure while the condition
exists.
Is the fuel system pressure within specifications?

380 kPa

(55 psi)

Go to Step 8

Go to Step 17

Check the in-line fuel filter.
Is the filter dirty or plugged?

–

Go to Step 18

Go to Step 9

Perform an injector diagnosis.
Did the injector diagnosis pinpoint the problem?

–

Go to Step 19

Go to Step 10

1. Check for proper ignition voltage output using a

spark tester.

2. Inspect the spark plugs for cracks, wear, improper

gap, burned electrodes, or heavy deposits.

Is the problem found?

–

Go to Step 11

Go to Step 12

Repair or replace any ignition system components
as needed.
Is the repair complete?

–

System OK

–

1. Inspect the ECM grounds for being clean, tight,

and in their proper locations.

2. Inspect the vacuum lines for kinks or leaks.
Is the problem found?

–

Go to Step 13

Go to Step 14

ENGINE CONTROLS 1F – 287

Surges or Chuggles (Cont’d)

Step

Action

Value(s)

Yes

Repair the electrical connections or the vacuum
lines as needed.
Is the repair complete?

–

System OK

–

Check the generator output voltage.
Is the generator voltage within the value specified?

12–16 V

Go to Step 16

Go to Step 15

Repair the generator.
Is the repair complete?

–

System OK

–

1. Check for intermittent Electric Exhaust Gas

Recirculation (EEGR) valve operation.

2. Repair or replace any components as needed.
Is the repair complete?

–

System OK

–

Repair the fuel system as needed.
Is the repair complete?

–

System OK

–

Replace the fuel filter.
Is the repair complete?

–

System OK

–

Replace the leaking or restricted fuel injectors.
Is the repair complete?

–

System OK

–

1F – 288 ENGINE CONTROLS

LACK OF POWER, SLUGGISHNESS, OR SPONGINESS

Definition: The engine delivers less than expected pow-
er. There is little or no increase in speed when the accel-
erator pedal is partially applied.

Step

Action

Value(s)

Yes

Were the Important Preliminary Checks performed?

–

Go to Step 2

Go to

“Important

Preliminary

Checks”

1. Verify the customer’s complaint.
2. Compare the performance of the customer’s

vehicle with a similar unit.

Does the problem exist?

–

Go to Step 3

System OK

1. Inspect the air filter for excessive contamination.
2. Replace the air filter as needed.
3. Check the transaxle shift pattern and down shift

operation.

Does the transaxle operate properly?

–

Go to Step 4

Go to Step 5

Check the fuel system pressure.
Is the fuel system pressure within specifications?

380 kPa

(55 psi)

Go to Step 7

Go to Step 6

Repair the transaxle as needed.
Is the repair complete?

–

System OK

–

Repair the fuel system as needed.
Is the repair complete?

–

System OK

–

Check for a restricted fuel filter or contaminated fuel.
Is the problem found?

–

Go to Step 8

Go to Step 9

Repair or replace any components as needed.
Is the repair complete?

–

System OK

–

1. Check the ignition system output for all of the

cylinders using a spark tester.

2. Check for proper ignition control operation.
Is the ignition system operating properly?

–

Go to Step 10

Go to Step 11

1. With the engine at normal operating temperature,

connect a vacuum gauge to a vacuum port on the
intake manifold.

2. Operate the engine at 1000 rpm.
3. Record the vacuum reading.
4. Increase the engine speed to 2500 rpm.
5. Note the vacuum reading at a steady 2500 rpm.
Does the vacuum decrease more than the value
specified?

10 kPa

(3 in Hg)

Go to Step 12

Go to Step 15

Repair or replace any ignition system components
as needed.
Is the repair complete?

–

System OK

–

Inspect the exhaust system for restrictions and
damaged or collapsed pipes.
Is the problem found?

–

Go to Step 13

Go to Step 14

Repair or replace any components as needed.
Is the repair complete?

–

System OK

–

1. Check the cylinder compression and valve timing.
2. Inspect the camshaft for excessive wear.
Is the problem found?

–

Go to Step 15

Go to Step 16

ENGINE CONTROLS 1F – 289

Lack of Power, Sluggishness, or Sponginess (Cont’d)

Step

Action

Value(s)

Yes

Repair or replace any engine components as
needed.
Is the repair complete?

–

System OK

–

1. Check the Engine Control Module (ECM) grounds

for being clean, tight, and in their proper location.

2. Check the exhaust recirculation valve for being

open or partially open all the time.

3. Check the torque converter clutch operation.
4. Check the A/C system operation.
5. Check the generator output.
6. Repair the generator if the output is not within the

specified range.

Are all checks and repairs complete?

12–16 V

System OK

–

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