ENGINE CONTROLS 1F – 11
DAEWOO V–121 BL4
FUEL SYSTEM SPECIFICATIONS
Gasoline
All engines are designed to use unleaded fuel only. Un-
leaded fuel must be used for proper emission control sys-
tem operation. Its use will also minimize spark plug fouling
and extend engine oil life. Using leaded fuel can damage
the emission warranty coverage. The fuel should meet
specification ASTM D4814 for the U.S. or CGSB 3.5 M93
for Canada. All engines are designed to use unleaded fuel
with a minimum U(R+M)/2e (pump) octane number of 87,
where R=research octane number, and M=motor octane
number.
Ethanol
You may use fuel containing ethanol (ethyl alcohol) orgrain alcohol providing that there is no more than 10 per-
cent ethyl alcohol by volume.
Methanol
Do not use fuels containing methanol. Methanol can cor-
rode metal parts and cause damage to plastic and rubber
parts in the fuel system.
Methyl Tertiary–Butyl Ether (MTBE)
You may use fuel containing Methyl Tertiary–Butyl Ether
(MTBE) providing there is no more than 15 percent MTBE
by volume.
TEMPERATURE VS RESISTANCE
°C°FECT SensorIAT Sensor
OHMS
Temperature vs Resistance Values (Approximate)
100212177187
90194241246
80176332327
70158467441
60140667603
50122973837
4511 31188991
4010414591180
359518021412
308622381700
257727962055
206835202500
155944503055
105056703760
54172804651
03294205800
–523123007273
–1014161809200
–155214509200
–20–42868015080
–30–225270025600
–40–4010070045300
1F – 26IENGINE CONTROLS
DAEWOO V–121 BL4
T3B11F15
Front Heated Oxygen Sensor
(HO2S1) Connector
234 1
T3D11F47
EVAP Canister
Purge Solenoid
Connector
12
1F – 28IENGINE CONTROLS
DAEWOO V–121 BL4
COMPONENT LOCATOR
COMPONENT LOCATOR (1.4L/1.6L DOHC)
Components on ECM Harness
11. Engine Control Module (ECM)
12. Data Link Connector (DLC)
13. Malfunction Indicator Lamp (MIL)
14. ECM/ABS Harness Ground
15. Fuse Panel (2)
ECM Controlled Devices
20. Exhaust Gas Recirculation (EGR) Valve
21. Fuel Injector (4)
22. Main Throttle Idle Actuator (MTIA)
23. Fuel Pump Relay
24. Cooling Fan Relays (High)
25. Cooling Fan Control Relay (A/C Only)
26. Electronic Ignition System Ignition Coil
27. Evaporative Emission (EVAP) Control Purge Sole-
noid
28. Main Relay
29. A/C Compressor Relay30. Cooling Fan Relays (Low)
Information Sensors
31. Manifold Absolute Pressure (MAP) Sensor
32. Front Heated Oxygen Sensor (HO2S1)
33. Variable Geometry Induction System (VGIS) Sole-
noid
34. Engine Coolant Temperature (ECT) Sensor
35. Intake Air Temperature (IAT) Sensor
36. Vehicle Speed Sensor (VSS)
38. Crankshaft Position (CKP) Sensor
39. Knock Sensor
40. Rear Heated Oxygen Sensor (HO2S2)
41. Camshaft Position (CMP) Sensor
Not PCM/ECM Connected
42. Evaporative Emission Canister (under vehicle, be-
hind right rear wheel)
43. Engine Oil Pressure Switch
44. Air Cleaner
ENGINE CONTROLS 1F – 29
DAEWOO V–121 BL4
COMPONENT LOCATOR (1.8L DOHC)
Components on ECM Harness
11. Engine Control Module (ECM)
12. Data Link Connector (DLC)
13. Malfunction Indicator Lamp (MIL)
14. ECM/ABS Harness Ground
15. Fuse Panel (2)
ECM Controlled Devices
20. Exhaust Gas Recirculation (EGR) Valve
21. Fuel Injector (4)
22. Idle Air Control (IAC) Valve
23. Fuel Pump Relay
24. Cooling Fan Relays (High)
25. Cooling Fan Control Relay (A/C Only)
26. Electronic Ignition System Ignition Coil
27. Evaporative Emission (EVAP) Control Purge Sole-
noid
28. Main Relay
29. A/C Compressor Relay30. Cooling Fan Relays (Low)
Information Sensors
31. Manifold Absolute Pressure (MAP) Sensor
32. Front Heated Oxygen Sensor (HO2S1)
33. Throttle Position (TP) Sensor
34. Engine Coolant Temperature (ECT) Sensor
35. Intake Air Temperature (IAT) Sensor
36. Vehicle Speed Sensor (VSS)
38. Crankshaft Position (CKP) Sensor
39. Knock Sensor
40. Rear Heated Oxygen Sensor (HO2S2)
41. Camshaft Position (CMP) Sensor
Not PCM/ECM Connected
42. Evaporative Emission Canister (under vehicle, be-
hind right rear wheel)
43. Engine Oil Pressure Switch
44. Air Cleaner
1F – 30IENGINE CONTROLS
DAEWOO V–121 BL4
DIAGNOSIS
SYSTEM DIAGNOSIS
DIAGNOSTIC AIDS
If an intermittent problem is evident, follow the guidelines
below.
Preliminary Checks
Before using this section you should have already per-
formed the ”On–Board Diagnostic System Check.”
Perform a thorough visual inspection. This inspection can
often lead to correcting a problem without further checks
and can save valuable time. Inspect for the following con-
ditions:
S Engine control module (ECM) grounds for being
clean, tight, and in their proper location.
S Vacuum hoses for splits, kinks, collapsing and prop-
er connections as shown on the Vehicle Emission
Control Information label. Inspect thoroughly for
any type of leak or restriction.
S Air leaks at the throttle body mounting area and the
intake manifold sealing surfaces.
S Ignition wires for cracks, hardness, proper routing,
and carbon tracking.
S Wiring for proper connections.
S Wiring for pinches or cuts.
Diagnostic Trouble Code Tables
Do not use the Diagnostic Trouble Code (DTC) tables to
try to correct an intermittent fault. The fault must be pres-
ent to locate the problem.
Incorrect use of the DTC tables may result in the unneces-
sary replacement of parts.
Faulty Electrical Connections or Wiring
Most intermittent problems are caused by faulty electrical
connections or wiring. Perform a careful inspection of sus-
pect circuits for the following:
S Poor mating of the connector halves.
S Terminals not fully seated in the connector body.
S Improperly formed or damaged terminals. All con-
nector terminals in a problem circuit should be care-
fully inspected, reformed, or replaced to insure con-
tact tension.S Poor terminal–to–wire connection. This requires
removing the terminal from the connector body.
Road Test
If a visual inspection does not find the cause of the prob-
lem, the vehicle can be driven with a voltmeter or a scan
tool connected to a suspected circuit. An abnormal voltage
or scan tool reading will indicate that the problem is in that
circuit.
If there are no wiring or connector problems found and a
DTC was stored for a circuit having a sensor, except for
DTC P0171 and DTC P0172, replace the sensor.
Fuel System
Some intermittent driveability problems can be attributed
to poor fuel quality. If a vehicle is occasionally running
rough, stalling, or otherwise performing badly, ask the cus-
tomer about the following fuel buying habits:
S Do they always buy from the same source? If so,
fuel quality problems can usually be discounted.
S Do they buy their fuel from whichever fuel station
that is advertising the lowest price? If so, check the
fuel tank for signs of debris, water, or other contam-
ination.
IDLE LEARN PROCEDURE
Whenever the battery cables, the engine control module
(ECM), or the ECM fuse is disconnected or replaced, the
following idle learn procedure must be performed:
1. Turn the ignition ON for 5 seconds.
2. Turn the ignition OFF for 5 seconds.
3. Turn the ignition ON for 5 seconds.
4. Start the engine in park/neutral.
5. Allow the engine to run until the engine coolant is
above 185° F (85°C ).
6. Turn the A/C ON for 10 seconds, if equipped.
7. Turn the A/C OFF for 10 seconds, if equipped.
8. If the vehicle is equipped with an automatic trans-
axle, apply the parking brake. While pressing the
brake pedal, place the transaxle in D (drive).
9. Turn the A/C ON for 10 seconds, if equipped.
10. Turn the A/C OFF for 10 seconds, if equipped.
11. Turn the ignition OFF. The idle learn procedure is
complete.
ENGINE CONTROLS 1F – 33
DAEWOO V–121 BL4
On–Board Diagnostic (EOBD) System Check (1.4L/1.6L DOHC)
StepActionValue(s)YesNo
11. Turn the ignition switch to ON.
2. Observe the Malfunction Indicator Lamp (MIL).
Is the MIL illuminate?–Go to Step 2Go to
”No Malfunction
Indicator Lamp”
21. Turn the ignition switch to LOCK.
2. Install the scan tool to the Data link Connector
(DLC).
3. Turn the ignition switch to ON.
4. Attempt to display the Engine Control Module
(ECM) engine data with the scan tool.
Does the scan tool display the ECM engine data?–Go to Step 3Go to Step 8
31. Using the scan tool output test function, select
the MIL lamp control and command the MIL off.
2. Observe the MIL.
Does the MIL turn OFF?–Go to Step 4Go to
”Malfunction In-
dicator Lamp
on Steady”
4Attempt to start the engine.
Does the engine start and continue to run?–Go to Step 5Go to
”Engine Cranks
But Will Not
Run”
5Select DISPLAY DTC with the scan tool.
Are any Diagnostic Trouble Codes (DTCs) stored?–Go to Step 6Go to Step 7
6Check the display for DTCs P0107, P0108, P0113,
P0118, P0122, P0123, P0712, P1392.
Are two or more of the following DTCs stored?–Go to
”Multiple ECM
Information
Sensor DTCs
Set”Go to applica-
ble DTC table
7Compare the ECM data values displayed on the
scan tool to the typical engine scan data values.
Are the displayed values normal or close to the typi-
cal values?–Go to
”ECM Output
Diagnosis”Go to indicated
component
system check
81. Turn the ignition switch to LOCK.
2. Disconnect the ECM connector.
3. Turn the ignition switch to ON.
4. Check the serial data circuit for an open, short
to ground, or short to voltage. Also check the
DLC ignition feed circuit for an open or short to
ground, and check the DLC ground circuits for
an open.
Is a problem found?–Go to Step 9Go to Step 10
9Repair the open, short to ground, or short to voltage
in the serial data circuit or the DLC ignition feed cir-
cuit.
Is the repair complete?–System OK–
101. Attempt to reprogram the ECM.
2. Attempt to display the ECM data with the scan
tool.
Does the scan tool display ECM engine data?–Go to Step 2Go to Step 11
11Replace the ECM.
Is the replacement complete?–System OK–
ENGINE CONTROLS 1F – 35
DAEWOO V–121 BL4
On–Board Diagnostic (EOBD) System Check (1.8L DOHC)
StepActionValue(s)YesNo
11. Turn the ignition switch to ON.
2. Observe the Malfunction Indicator Lamp (MIL).
Is the MIL illuminate?–Go to Step 2Go to
”No Malfunction
Indicator Lamp”
21. Turn the ignition switch to LOCK.
2. Install the scan tool to the Data link Connector
(DLC).
3. Turn the ignition switch to ON.
4. Attempt to display the Engine Control Module
(ECM) engine data with the scan tool.
Does the scan tool display the ECM engine data?–Go to Step 3Go to Step 8
31. Using the scan tool output test function, select
the MIL lamp control and command the MIL off.
2. Observe the MIL.
Does the MIL turn OFF?–Go to Step 4Go to
”Malfunction In-
dicator Lamp
on Steady”
4Attempt to start the engine.
Does the engine start and continue to run?–Go to Step 5Go to
”Engine Cranks
But Will Not
Run”
5Select DISPLAY DTC with the scan tool.
Are any Diagnostic Trouble Codes (DTCs) stored?–Go to Step 6Go to Step 7
6Check the display for DTCs P0107, P0108, P0113,
P0118, P0122, P0123, P0712, P1392.
Are two or more of the following DTCs stored?–Go to
”Multiple ECM
Information
Sensor DTCs
Set”Go to applica-
ble DTC table
7Compare the ECM data values displayed on the
scan tool to the typical engine scan data values.
Are the displayed values normal or close to the typi-
cal values?–Go to
”ECM Output
Diagnosis”Go to indicated
component
system check
81. Turn the ignition switch to LOCK.
2. Disconnect the ECM connector.
3. Turn the ignition switch to ON.
4. Check the serial data circuit for an open, short
to ground, or short to voltage. Also check the
DLC ignition feed circuit for an open or short to
ground, and check the DLC ground circuits for
an open.
Is a problem found?–Go to Step 9Go to Step 10
9Repair the open, short to ground, or short to voltage
in the serial data circuit or the DLC ignition feed cir-
cuit.
Is the repair complete?–System OK–
101. Attempt to reprogram the ECM.
2. Attempt to display the ECM data with the scan
tool.
Does the scan tool display ECM engine data?–Go to Step 2Go to Step 11
11Replace the ECM.
Is the replacement complete?–System OK–
1F – 36IENGINE CONTROLS
DAEWOO V–121 BL4
MULTIPLE ECM INFORMATION SENSOR DTCS SET
Circuit Description
The Engine Control Module (ECM) monitors various sen-
sors to determine engine operating conditions. The ECM
controls fuel delivery, spark advance, transaxle operation,
and emission control device operation based on the sen-
sor inputs.
The ECM provides a sensor ground to all of the sensors.
The ECM applies 5 volts through a pull–up resistor and
monitors the voltage present between the sensor and the
resistor to determine the status of the Engine Coolant
Temperature (ECT) sensor, the Intake Air Temperature
(IAT) sensor. The ECM provides the Exhaust Gas Recir-
culation (EGR) Pintle Position Sensor, the Throttle Posi-
tion (TP) sensor, the Manifold Absolute Pressure (MAP)
sensor, and the Fuel Tank Pressure Sensor with a 5 volt
reference and a sensor ground signal. The ECM monitors
the separate feedback signals from these sensors to de-
termine their operating status.
Diagnostic Aids
Be sure to inspect the ECM and the engine grounds for be-
ing secure and clean.
A short to voltage in one of the sensor circuits can cause
one or more of the following DTCs to be set: P0108,
P0113, P0118, P0123, P1106, P1111, P1115, P1121,
P0463, P0533.
If a sensor input circuit has been shorted to voltage, en-
sure that the sensor is not damaged. A damaged sensor
will continue to indicate a high or low voltage after the af-
fected circuit has been repaired. If the sensor has been
damaged, replace it.
An open in the sensor ground circuit between the ECM and
the splice will cause one or more of the following DTCs to
be set: P0107, P0108, P0113, P0118, P0122, P0123,
P1106, P1111, P1115, P1121, P0462, P0532.
A short to ground in the 5 volt reference circuit or an open
in the 5 volt reference circuit between the ECM and the
splice will cause one or more of the following DTCs to be
set: P0107, P0112, P0117, P0122, P1107, P1112, P1114,
P1122, P0462, P0532.Check for the following conditions:
S Inspect for a poor connection at the ECM. Inspect
harness connectors for backed–out terminals, im-
proper mating, broken locks, improperly formed or
damaged terminals, and poor terminal–to–wire con-
nection.
S Inspect the wiring harness for damage. If the har-
ness appears to be OK, observe an affected sen-
sor ’s displayed value on the scan tool with the igni-
tion ON and the engine OFF while moving
connectors and wiring harnesses related to the af-
fected sensors. A change in the affected sensor’s
displayed value will indicate the location of the fault.
Test Description
Number(s) below refer to the step number(s) on the Diag-
nostic Table.
1. The Powertrain On–Board Diagnostic (EOBD) Sys-
tem Check prompts the technician to complete
some basic checks and store the freeze frame and
failure records data on the scan tool if applicable.
This creates an electronic copy of the data taken
when the malfunction occurred. The information is
then stored on the scan tool for later reference.
9. A faulty EGR valve can leak a small amount of cur-
rent from the ignition feed circuit to the 5 volt refer-
ence circuit. If the problem does not exist with the
EGR valve disconnected, replace the EGR valve.
0. If a sensor input circuit has been shorted to voltage,
ensure that the sensor has not been damaged. A
damaged IAT or ECT sensor will continue to indi-
cate a high voltage or low temperature after the
affected circuit has been repaired. A damaged ACT,
TP, MAP, Fuel Tank Pressure, or EGR Pintle Posi-
tion sensor will indicate a high or low voltage or
may be stuck at a fixed value after the affected cir-
cuit has been repaired. If the sensor has been dam-
aged, replace it.
21. The replacement ECM must be reprogrammed.
Refer to the latest Techline procedure for ECM re-
programming.