Daewoo Matiz (2003 year). Manual - part 56

1F – 134  ENGINE CONTROLS

MAA1F160

ENGINE CONTROLS  1F – 135

DIAGNOSTIC TROUBLE CODE (DTC) – P0300 MULTIPLE CYLINDER MISFIRE

System Description

The Engine Control Module (ECM) monitors the crank-
shaft and camshaft positions to detect if the engine is
misfiring. The ECM looks for a quick drop in crankshaft
speed. This test is executed in blocks of 100 engine rev-
olution tests. It may take between one to several tests to
store a Diagnostic Trouble Code (DTC) and illuminate
the Malfunction Indicator Lamp (MIL). Under light misfire
conditions, it may also take more than one trip to set a
DTC. Severe misfire will flash the MIL, indicating that
catalyst damage is possible.

Conditions for Setting the DTC

D

Emission threshold is 3.0% for manual transaxle.

D

20 engine cycles have occurred since cranking has
started.

D

A/C compressor clutch has not just engaged or disen-
gaged.

D

Engine load and engine speed are in a detectable re-
gion and are at or above zero torque.

D

Camshaft Position (CMP) sensor is in synchroniza-
tion.

D

Electric Exhaust Gas Recirculation (EEGR) flow
diagnostic is not in progress.

D

Fuel level is greater than or equal to 20% of rated
tank capacity.

D

Decel Fuel Cutoff (DFCO) not active.

D

Fuel is not shutoff from high engine speed of 6500
rpm for manual transaxle vehicle.

D

Fuel is not shutoff at 255 km/h (158 mph).

D

Throttle position change is less than 3% per 125 ms.

D

Vehicle has not encountered an abusive engine
speed of 7000 rpm.

D

Crankshaft speed patters are normal.

D

Throttle position is less than 4% when vehicle speed
is greater than 10 km/h (6 mph).

D

Engine speed is between 800 and 4500 rpm.

D

Vehicle voltage is between 11 and 16 volts.

D

Engine Coolant Temperature (ECT) is between –7

°

C

(20

°

F) and 120

°

C (248

°

F).

D

The engine speed is less than or equal to 1800 rpm or
the crank angle sensing error has not been learned.

D

There is the correct ratio between Crankshaft Posi-
tion (CKP) sensor pulses and CMP sensor pulses.

D

DTCs P0106, P0107, P0108, P0117, P0118, P0122,
P0123, P0320, P0337, P0341, P0342 and P0502 are
not set.

Action Taken when the DTC Sets

D

The malfunction Indicator Lamp (MIL) will blinking.

D

The ECM will record operating conditions at the time
the diagnostic fails. The information will be stored in
the Freeze Frame and failure records buffers.

D

A history DTC is stored.

Conditions for Clearing the MIL/DTC

D

A history DTC will clear after 40 consecutive warm up
cycles without a fault.

D

DTC(s) can be cleared by using the scan tool.

Diagnostic Aids

An intermittent can also be the result of a defective re-
luctor wheel. Remove the CKP sensor and inspect the
reluctor wheel through the sensor mount hole. Check for
porosity and the condition of wheel. If the DTC is inter-
mittent refer to “Symptoms Diagnosis” in this section.

DTC P0300 – Multiple Cylinder Misfire

Step

Action

Value(s)

Yes

No

1

Perform an Euro On-Board Diagnostic (EOBD)
System Check.
Was the check performed?

–

Go to Step 2

Go to

“On-Board
Diagnostic

System Check”

2

1. Install a scan tool to the Data Link Connector

(DLC).

2. Turn the ignition ON, with the engine OFF.
3. Request Diagnostic Trouble Codes (DTCs)
Are DTCs P0201, P0202, P0203, P0204 set?

–

Go to

Applicable DTC

table

Go to Step 3

3

Perform a visual/physical inspection.
Make any repairs that are necessary.
Is the repair complete?

–

Go to Step 27

Go to Step 4

4

Start the engine and allow it to idle.
Are any Misfire Current counters incrementing?

–

Go to Step 5

Go to Step 6

5

Are all counters equal (within a percentage of each
other)?

–

Go to Step 7

Go to Step 11

1F – 136  ENGINE CONTROLS

DTC P0300 – Multiple Cylinder Misfire (Cont’d)

Step

Action

Value(s)

Yes

No

6

1. Turn the ignition ON, with the engine OFF.
2. Review the Freeze Frame data, and note the

parameters.

3. Operate the vehicle within the Freeze Frame

conditions and conditions for setting this DTC as
noted.

Are any Misfire Current counters incrementing?

–

Go to Step 5

Go to

“Diagnostic

Aids”

7

1. Turn the engine OFF.
2. Install a fuel pressure gauge to the fuel rail.
3. Observe the fuel pressure with the engine

running.

Is the fuel pressure within the specified value?

284–325 kPa

(41–47 psi)

Go to Step 8

Go to

“Fuel System

Diagnosis”

8

Check the fuel for contamination.
Is the fuel OK?

–

Go to Step 9

Go to Step 10

9

Check for a basic engine problem and repair as
necessary.
Is the repair complete?

–

Go to Step 27

–

10

Replace the contaminated fuel.
Is the repair complete?

–

Go to Step 27

–

11

1. Turn the engine OFF.
2. Disconnect the fuel injector harness connector.
3. Install a spark tester on cylinder #1 spark plug

cable.

4. Crank the engine and check for spark.
5. Repeat the above procedure on cylinders #2, #3.
Is a spark observed on all four spark plug cables?

–

Go to Step 12

Go to Step 20

12

Replace any malfunctioning spark plugs if
necessary.
Is the repair complete?

–

Go to Step 27

Go to Step 13

13

1. Turn the engine OFF.
2. Disconnect the fuel injector connectors from the

injectors.

3. Install an injector test light on the injector harness

connector for the cylinders that had misfired.

4. Crank the engine and note the test light.
Does the injector test light blink?

–

Go to Step 14

Go to Step 15

14

Perform the Fuel Injector Balance Test.
Are the fuel injectors OK?

–

Go to Step 9

Go to Step 16

15

1. Disconnect the injector test light.
2. With a test light connected to ground, probe the

ignition feed terminal 1 of the injector harness
connector for each cylinder that had misfire.

3. Crank the engine.
Does the test light illuminate?

–

Go to Step 17

Go to Step 19

16

Replace any malfunctioning fuel injectors.
Is the repair complete?

–

Go to Step 27

–

17

Check the affected fuel injector driver circuit at
terminals 90, 58 and 89 for an open, short, or short
to voltage.
Is a problem found?

–

Go to Step 18

Go to Step 24

ENGINE CONTROLS  1F – 137

DTC P0300 – Multiple Cylinder Misfire (Cont’d)

Step

Action

Value(s)

Yes

No

18

Repair the open or the shorted fuel injector driver
circuit.
Is the repair complete?

–

Go to Step 27

–

19

Repair the open ignition feed circuit between the fuel
injector harness connector and the fuel injector
connector.
Is the repair complete?

–

Go to Step 27

–

20

Measure the resistance of the spark plug cable that
the spark plug tester did not spark.
Is the resistance of the spark plug cable less than
the specified value?

30000

Ω

Go to Step 21

Go to Step 25

21

Inspect the Engine Control Module (ECM) connector
and connections.
Are the connections OK?

–

Go to Step 22

Go to Step 23

22

Check the affected cylinders ignition control circuit
for an open or short and repair as necessary.
Is the repair complete?

–

Go to Step 27

Go to Step 26

23

Repair the connector or connections.
Is the repair complete?

–

Go to Step 27

–

24

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

–

Go to Step 27

–

25

Replace the spark plug cable.
Is the repair complete?

–

Go to Step 27

–

26

Replace the faulty ignition coil.
Is the repair complete?

–

Go to Step 27

Go to Step 24

27

1. Using the scan tool, clear the DTCs.
2. Start the engine and idle at normal operating

temperature.

3. Operate the vehicle within the conditions for

setting this DTC as supported in the text.

Does the scan tool indicate that this diagnostic ran
and passed?

–

Go to Step 28

Go to Step 2

28

Check if any additional DTCs are set.
Are any DTCs displayed that have not been
diagnosed?

–

Go to

Applicable DTC

table

System OK