Content .. 91 92 93 94 ..

Daewoo Matiz (2003 year). Manual - part 93

1F – 282 ENGINE CONTROLS

Intermittent (Cont’d)

Step

Action

Value(s)

Yes

1. Turn the ignition OFF.
2. Replace the ECM.
Is the repair complete?

–

System OK

–

Does the vehicle stall while driving?

–

Go to Step 11

Go to Step 12

Monitor the oxygen sensor and the injector base
pulse width with the scan tool.
Does the scan tool display a steady low voltage
(about 0 millivolts) for the oxygen sensor with the
control module commanding an injector base pulse
width of the value specified?

8 ms

Go to Step 9

Go to Step 12

1. Check for an open diode across the A/C clutch

and for other open diodes.

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

–

System OK

–

ENGINE CONTROLS 1F – 283

HARD START

Definition: The engine cranks OK, but does not start for
a long time. The engine eventually runs or may start and
immediately die.

Important: Ensure that the driver is using the correct
starting procedure. Before diagnosing, 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”

1. Connect the scan tool to the Data Link Connector

(DLC).

2. Check the Engine Coolant Temperature (ECT)

sensor and the Intake Air Temperature (IAT)
sensor using the scan tool.

3. Compare the coolant temperature and the IAT

with the ambient temperature when the engine is
cold.

Do the ECT and the IAT readings differ from the
ambient temperature by more than the value
specified?

C (5

Go to Step 3

Go to Step 4

1. Measure the resistance of the ECT sensor and

the IAT sensor.

2. Compare the resistance value to specifications

using the Temperature Vs. Resistance tables for
DTCs P0118 and P0113.

3. If the resistance is not the same, replace the

faulty sensor.

Is the repair complete?

–

System OK

–

1. Check for a sticking throttle shaft or a binding

linkage that may cause a high Throttle Position
(TP) sensor voltage. Repair or replace as
needed.

2. Check the TP sensor voltage reading with the

throttle closed.

Does the voltage measure within the value
specified?

0.4–0.8 V

Go to Step 5

Go to Step 26

1. Check the Manifold Absolute Pressure (MAP)

sensor response and accuracy.

2. Replace the MAP sensor as needed.
Is the repair complete?

–

System OK

Go to Step 6

Check the fuel pump operation.
Does the fuel pump operate for the specified time
when the ignition switch is turned ON?

2 sec

Go to Step 7

Go to “Fuel

Pump Relay

Circuit Check”

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

380 kPa

(55 psi)

Go to Step 8

Go to Step 27

Check for water contamination in the fuel.
Is fuel contaminated?

–

Go to Step 9

Go to Step 10

Replace the contaminated fuel.
Is the repair complete?

–

System OK

–

1F – 284 ENGINE CONTROLS

Hard Start (Cont’d)

Step

Action

Value(s)

Yes

1. Check the fuel injector driver circuit.
2. Disconnect all of the fuel injector harness

connectors at the fuel injectors.

3. Connect an injector test light between the

harness terminals of each fuel injector connector.

4. Note the test light while cranking the engine.
Does the test light blink at all connectors?

–

Go to Step 13

Go to Step 11

Check the fuel injector driver wiring harness, the
connectors, and the connector terminals for the
proper connections.
Is the problem found?

–

Go to Step 12

Go to Step 28

Repair the wiring harness, the connector, or the
connector terminal as needed.
Is the repair complete?

–

System OK

–

Measure the resistance of each fuel injector.
Is the fuel injector resistance within the value
specified at 20

C (68

Note: The resistance will increase slightly at higher
temperatures)?

11.6–12.4

Ω

Go to Step 15

Go to Step 14

Replace any fuel injector with a resistance that is out
of specifications.
Is the repair complete?

–

System OK

–

Perform an injector diagnosis.
Is the problem found?

–

Go to Step 16

Go to Step 17

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

–

System OK

–

1. Check for the proper ignition voltage output for

each cylinder with a spark tester.

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

gap, burned electrodes, or heavy deposits.

3. Inspect the ignition wires for short conditions.
4. Inspect all of the ignition grounds for loose

connections.

5. Inspect the Engine Control Module (ECM) for the

proper operation.

Is the problem found?

–

Go to Step 18

Go to Step 19

Correct or replace any faulty ignition components.
Is the repair complete?

–

System OK

–

Does the engine misfire or cut out under load or at
idle?

–

Go to “Ignition

System Check”

Go to Step 20

Does the engine start, but then immediately stall?

–

Go to Step 21

Go to Step 23

1. Remove the Crankshaft Position (CKP) sensor.
2. Inspect for faulty connections and repair as

needed.

Is the problem found?

–

Go to Step 22

Go to Step 25

Repair the faulty connections as needed.
Is the repair complete?

–

System OK

–

ENGINE CONTROLS 1F – 285

Hard Start (Cont’d)

Step

Action

Value(s)

Yes

1. Check for the proper valve timing.
2. Check the cylinder compression.
3. Inspect the pushrods, the rocker arms, the valve

springs, and the camshaft lobes for excessive
wear.

4. Inspect the intake manifold and the exhaust

manifold passages for casting flash.

Is the problem found?

–

Go to Step 24

Go to Step 25

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

–

System OK

–

Check the idle air control valve operation. Repair or
replace components as needed.
Is the repair complete?

–

System OK

–

Check the throttle position sensor circuit for proper
operation. Repair or replace components as needed.
Is the repair complete?

–

System OK

–

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

–

System OK

–

1. Turn the ignition OFF.
2. Replace the ECM.
Is the repair complete?

–

System OK

–

Content .. 91 92 93 94 ..