1A–12 GENERAL ENGINE INFORMATION
DAEWOO M-150 BL2
CHECKING ENGINE TIMING BELT
After checking the timing belt for looseness, crack, wear
or tension, replace the belt if necessary.
CHECKING ACCESSORY BELT
After checking the alternator belt (e), air conditioning/
power steering belt (f), air conditioning belt (g), power
steering belt (h), for looseness, crack, wear or tension,
replace the belt if necessary.
D102A304
CHECKING SPARK PLUG
After checking the spark plug for bad clearance, exces-
sive carbon deposit, worn electrode or damaged insula-
tor, replace the new one if necessary.
Remove and check the spark plug as follows ;
1. Pull the high tension cable cap portion (i), and discon-
nect the high tension cable from the spark plug.
If pulling the high tension cable (j), circuit could be
disconnected. Therefore, the cap portion should be
used.
D102A305
2. Remove the spark plugs from cylinder head using a
wrench.
3. Measure the spark plug clearance (k) with the filler
gauge. If measured value is not within the specified
value, adjust the grounding electrode.
When installing new spark plug, check the clearance
for equality and install it.
D102A306
ENGINE CONTROLS 1F–45
DAEWOO M-150 BL2
IGNITION SYSTEM CHECK
Circuit Description
The Electronic Ignition (EI) system uses a waste spark
method of spark distribution. In this type of EI system,
the Crankshaft Position (CKP) sensor is mounted to the
oil pump near a slotted wheel that is a part of the crank-
shaft pulley. The CKP sensor sends reference pulses to
the Engine Control Module (ECM). The ECM then trig-gers the EI system ignition coil. Each cylinder is individu-
al with coil per cylinder in sequence.
This leaves the remainder of the high voltage to be used
to fire the spark plug in the cylinder on its compression
stroke. Since the CKP sensor is in a fixed position, tim-
ing adjustments are not possible or needed.
Ignition System Check
Caution: Use only electrically insulated pliers when
handling ignition wires with the engine running to
prevent an electrical shock.
StepActionValue(s)YesNo
1
1. Remove the spark plugs.
2. Inspect for wet spark plugs, cracks, wear,
improper gap, burned electrodes, or heavy
deposits.
3. Replace the spark plugs as needed.
Is the repair complete?
–
System OKGo to Step 2
2
Check for the presence of spark from all of the
ignition wires while cranking the engine.
Is spark present from all of the ignition wires?
–
System OKGo to Step 3
3
1. Measure the resistance of the ignition wires.
2. Replace any ignition wire(s) with a resistance
above the value specified.
3. Check for the presence of spark from all of the
ignition wires.
Is spark present from all of the ignition wires?
30000 ΩSystem OKGo to Step 4
4Is spark present from at least one of the ignition
wires, but not all of the ignition wires?Go to Step 5Go to Step 12
5
1. Turn the ignition OFF.
2. Disconnect the Electronic Ignition (EI) system
ignition coil connector.
3. While cranking the engine, measure the voltage
at the EI system ignition coil connector terminal 1.
Does the voltage fluctuate within the values
specified?
0.2–2.0 VGo to Step 8Go to Step 6
6
Check for an open in the wire from EI system
ignition coil connector terminal 1 to the Engine
Control Module (ECM) connector terminal 66.
Is the problem found?
–
Go to Step 7Go to Step 11
7
1. Repair the wiring as needed.
2. Connect the EI system ignition coil connector.
3. Check for the presence of spark from all of the
ignition wires.
Is spark present from all of the ignition wires?
–
System OK
–
8
While cranking the engine, measure the voltage at
the EI system ignition coil connector terminal 2.
Does the voltage fluctuate within the values
specified?
0.2–2.0 VGo to Step 10Go to Step 9
1F–136 ENGINE CONTROLS
DAEWOO M-150 BL2
DTC P0300 – Multiple Cylinder Misfire (Cont’d)
StepActionValue(s)YesNo
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”
8Check the fuel for contamination.
Is the fuel OK?–Go to Step 9Go to Step 10
9
Check for a basic engine problem and repair as
necessary.
Is the repair complete?
–
Go to Step 27
–
10Replace 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 12Go to Step 20
12
Replace any malfunctioning spark plugs if
necessary.
Is the repair complete?
–
Go to Step 27Go 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 14Go to Step 15
14Perform the Fuel Injector Balance Test.
Are the fuel injectors OK?–Go to Step 9Go 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 17Go to Step 19
16Replace 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 18Go to Step 24
1F–140 ENGINE CONTROLS
DAEWOO M-150 BL2
DTC P0300 – Multiple Cylinder Misfire (Cont’d)
StepActionValue(s)YesNo
3
Perform a visual/physical inspection.
Make any repairs that are necessary.
Is the repair complete?–
Go to Step 27Go to Step 4
4Start the engine and allow it to idle.
Are any Misfire Current counters incrementing?–
Go to Step 5Go to Step 6
5Are all counters equal (within a percentage of each
other)?–Go to Step 7Go to Step 11
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”
8Check the fuel for contamination.
Is the fuel OK?–Go to Step 9Go to Step 10
9
Check for a basic engine problem and repair as
necessary.
Is the repair complete?
–
Go to Step 27
–
10Replace 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 12Go to Step 20
12
Replace any malfunctioning spark plugs if
necessary.
Is the repair complete?
–
Go to Step 27Go 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 14Go to Step 15
14Perform the Fuel Injector Balance Test.
Are the fuel injectors OK?–Go to Step 9Go 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 17Go to Step 19
1F–284 ENGINE CONTROLS
DAEWOO M-150 BL2
Hard Start (Cont’d)
StepActionValue(s)YesNo
10
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 13Go to Step 11
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 12Go to Step 28
12
Repair the wiring harness, the connector, or the
connector terminal as needed.
Is the repair complete?
–
System OK
–
13
Measure the resistance of each fuel injector.
Is the fuel injector resistance within the value
specified at 20C (68F)
Note: The resistance will increase slightly at higher
temperatures)?
11.6–12.4 ΩGo to Step 15Go to Step 14
14
Replace any fuel injector with a resistance that is out
of specifications.
Is the repair complete?
–
System OK
–
15Perform an injector diagnosis.
Is the problem found?–Go to Step 16Go to Step 17
16
Replace any restricted or leaking fuel injectors as
needed.
Is the repair complete?
–
System OK
–
17
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 18Go to Step 19
18Correct or replace any faulty ignition components.
Is the repair complete?–System OK–
19Does the engine misfire or cut out under load or at
idle?–Go to “Ignition
System Check”
Go to Step 20
20Does the engine start, but then immediately stall?–Go to Step 21Go to Step 23
21
1. Remove the Crankshaft Position (CKP) sensor.
2. Inspect for faulty connections and repair as
needed.
Is the problem found?
–
Go to Step 22Go to Step 25
22Repair the faulty connections as needed.
Is the repair complete?–System OK–
1F–286 ENGINE CONTROLS
DAEWOO M-150 BL2
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.
StepActionValue(s)YesNo
1
Were the Important Preliminary Checks performed?
–
Go to Step 2
Go to
“Important
Preliminary
Checks”
2
Connect the scan tool to the Data Link Connector
(DLC).
Does the oxygen sensor (O2S) respond quickly to
different throttle positions?
–
Go to Step 4Go to Step 3
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
–
4
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 7Go to Step 5
5
Is the long term fuel trim reading below the value
specified?
–20%
Go to
“Diagnostic Aids
for DTC P0172”
Go to Step 6
6
Is the long term fuel trim reading above the value
specified?
25%
Go to
“Diagnostic Aids
for DTC P0171”
–
7
Check the fuel system pressure while the condition
exists.
Is the fuel system pressure within specifications?
380 kPa
(55 psi)
Go to Step 8Go to Step 17
8Check the in-line fuel filter.
Is the filter dirty or plugged?–Go to Step 18Go to Step 9
9Perform an injector diagnosis.
Did the injector diagnosis pinpoint the problem?–Go to Step 19Go to Step 10
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 11Go to Step 12
11
Repair or replace any ignition system components
as needed.
Is the repair complete?
–
System OK
–
12
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 13Go to Step 14
1F–290 ENGINE CONTROLS
DAEWOO M-150 BL2
DETONATION/SPARK KNOCK
StepActionValue(s)YesNo
1
Were the Important Preliminary Checks performed?
–
Go to Step 2
Go to
“Important
Preliminary
Checks”
2
1. Fill the fuel tank with a known good grade of
gasoline that has the octane rating of the value
specified.
2. Reevaluate the vehicle’s performance.
Does the detonation problem still exist?
91 octaneGo to Step 3System OK
3
1. Inspect for low engine coolant level.
2. Check for restricted airflow to the radiator or
restricted coolant flow.
3. Check for a faulty thermostat.
4. Check for an incorrect coolant solution.
Is the problem found?
–
Go to Step 4Go to Step 5
4
Repair or replace any cooling system components
as needed.
Is the repair complete?
–
System OK
–
5
1. Check the engine coolant temperature using the
scan tool.
2. Replace the Engine Coolant Temperature (ECT)
sensor if the resistance is not within specifications
as listed in the Diagnostic Aids for diagnostic
trouble code P0118.
Is the problem found?
–
Go to Step 6Go to Step 7
6
Replace the ECT sensor or repair the circuit as
needed.
Is the repair complete?
–
System OK
–
7
1. Check the ignition system output with a spark
tester.
2. Inspect the spark plugs for the proper heat range
and gap.
3. Check for the proper operation of the ignition
controls.
Is the ignition system operating properly?
–
Go to Step 9Go to Step 8
8
Repair or replace the ignition system components as
needed.
Is the repair complete?
–
System Ok
–
9
1. Connect the scan tool to the Data Link Connector
(DLC).
2. Road test the vehicle at the speed of the
complaint.
3. Monitor the long term fuel trim reading from the
scanner data stream.
Is the long term fuel trim reading above the value
specified?
25%
Go to
“Diagnostic Aids
for DTC P0171”
Go to Step 10
10Check the fuel system pressure.
Is the problem found?380 kPa
(55 psi)
Go to Step 11Go to Step 12
11
Repair or replace the fuel system components as
needed.
Is the repair complete?
–
System OK
–
ENGINE CONTROLS 1F–293
DAEWOO M-150 BL2
Hesitation, Sag, Stumble (Cont’d)
StepActionValue(s)YesNo
13
Repair the restriction in the fuel system or replace
the faulty fuel pump.
Is the repair complete?
–
System OK
–
14
1. Check for faulty ignition wires.
2. Inspect for fouled spark plugs.
3. Check the ignition system output on each cylinder
with a spark tester.
Is the problem found?
–
Go to Step 15Go to Step 16
15
Repair or replace any ignition components as
needed.
Is the repair complete?
–
System OK
–
16
1. Check the generator output voltage.
2. Repair or replace the generator if the generator
output is less than the value specified.
3. Check the Electric Exhaust Gas Recirculation
(EEGR) valve operation.
Are all checks and needed repairs complete?
–
System OK
–