2004 DAEWOO LACETTI engine controls

ENGINE CONTROLS 1F – 599
DAEWOO V–121 BL4
8. Remove the fuel rail with the fuel injectors attached.
9. Remove the fuel injector retainer clips.
10. Remove the fuel injectors by pulling down and out.
11. Discard the fuel injector O–rings.
Installation Procedure
Important : Different injectors are calibrated for different
flow rates. When ordering new fuel injectors, be certain to
order the identical part number that is inscribed on the old
injector.
1. Lubricate the new fuel injector O–rings with engine
oil. Install the new O–rings on the fuel injectors.
2. Install the fuel injectors into the fuel rail sockets
with the fuel injector terminals facing outward.
3. Install the fuel injector retainer clips onto the fuel
injectors and the fuel rail ledge.
4. Make sure that the clip is parallel to the fuel injector
harness connector.
5. Install the fuel rail assembly into the cylinder head.
6. Install the fuel rail mounting bolts.
Tighten
Tighten the fuel rail mounting bolts to 25 NSm (18 lb–
ft).

1F – 600IENGINE CONTROLS
DAEWOO V–121 BL4
7. Connect the fuel feed hose.
8. Connect the fuel injector harness connectors. Ro-
tate each fuel injector as required to avoid stretch-
ing the wireing harness.
9. Install the intake manifold bracket with the bolts.
10. Connect the negative battery cable.
11. Perform a leak check of the fuel rail and fuel injec-
tors.
FUEL RAIL AND INJECTORS
(1.8L DOHC)
Removal Procedure
CAUTION : The fuel system is under pressure. To
avoid fuel spillage and the risk of personal injury or
fire, it is necessary to relieve the fuel system pressure
before disconnecting the fuel lines.
1. Relieve the fuel system pressure. Refer to ” Fuel
System Pressure Relief ” in this section.
2. Disconnect the negative battery cable.
3. Disconnect the intake air temperature (IAT) sensor
connector.
4. Disconnect the breather hose from the valve cover.
5. Disconnect the positive crankcase ventilation (PCV)
hose from the valve cover.
6. Disconnect the throttle cables from the throttle body
and the bracket.
7. Disconnect the fuel feed line at the fuel rail.
8. Remove the fuel rail retaining bolts.

ENGINE CONTROLS 1F – 601
DAEWOO V–121 BL4
Notice : Before removal, the fuel rail assembly may be
cleaned with a spray–type cleaner, following package in-
structions. Do not immerse the fuel rails in liquid cleaning
solvent. Use care in removing the fuel rail assembly to pre-
vent damage to the electrical connectors and the injector
spray tips. Prevent dirt and other contaminants from enter-
ing open lines and passages. Fittings should be capped
and holes plugged during service.
Important : If an injector becomes separated from the rail
and remains in the cylinder head, replace the injector O–
ring seals and the retaining clip.
9. Remove the fuel rail with the injectors attached.
10. Remove the fuel injector retainer clips.
11. Remove the fuel injectors by pulling them down and
out.
12. Discard the fuel injector O–rings.
Installation Procedure
Important : Different injectors are calibrated for different
flow rates. When ordering new fuel injectors, be certain to
order the identical part number that is inscribed on the old
injector.
1. Lubricate the new fuel injector O–rings with engine
oil. Install the new O–rings on the fuel injectors.
2. Install the fuel injectors into the fuel rail sockets
with the fuel injector terminals facing outward.
3. Install the fuel injector retaining clips onto the fuel
injector and the fuel rail ledge.
4. Make sure that the clips are parallel to the fuel in-
jector harness connector.
5. Install the fuel rail assembly into the cylinder head.
6. Install the fuel rail retaining bolts.
Tighten
Tighten the fuel rail retaining bolts to 25 NSm (18 lb–
ft).
7. Connect the fuel feed line to the fuel rail.
8. Connect the fuel injector connectors. Rotate each
fuel injector as required.

1F – 602IENGINE CONTROLS
DAEWOO V–121 BL4
9. Connect the PCV hose to the valve cover.
10. Connect the breather hose to the valve cover.
11. Connect the IAT sensor connector.
12. Connect the negative battery cable.
13. Perform a leak check of the fuel rail and fuel injec-
tors.
ENGINE COOLANT TEMPERATURE
SENSOR (1.4L/1.6L DOHC)
Removal Procedure
1. Relieve the coolant system pressure.
2. Disconnect the negative battery cable.
3. Disconnect the engine coolant temperature (ECT)
sensor connector.
Notice : Take care when handling the engine coolant tem-
perature sensor. Damage to the sensor will affect the prop-
er operation of the fuel injection system.
4. Remove the ECT sensor
Installation Procedure
1. Install the engine coolant temperature (ECT) sen-
sor.
Tighten
Tighten the engine coolant temperature (ECT) sensor
to 17.5 NSm (13 lb–ft).
2. Connect the ECT sensor connector.
3. Connect the negative battery cable.
ENGINE COOLANT TEMPERATURE
SENSOR (1.8L DOHC)
Removal Procedure
1. Relieve the coolant system pressure.
2. Disconnect the negative battery cable.
3. Disconnect the engine coolant temperature (ECT)
sensor connector.
Notice : Take care when handling the engine coolant tem-
perature sensor. Damage to the sensor will affect the prop-
er operation of the fuel injection system.
4. Remove the ECT sensor from the electronic ignition
(EI) system ignition coil adapter.

ENGINE CONTROLS 1F – 603
DAEWOO V–121 BL4
Installation Procedure
1. Coat the threads of the ECT sensor with sealer.
2. Install the ECT sensor into the EI system ignition
coil adapter.
Tighten
Tighten the engine coolant temperature sensor to 20
NSm (15 lb–ft).
3. Connect the ECT sensor connector.
4. Fill the coolant system.
5. Connect the negative battery cable.
THROTTLE POSITION SENSOR
(1.8L DOHC)
Removal Procedure
1. Disconnect the negative battery cable.
2. Remove the air intake tube and resonator.
3. Disconnect the throttle position (TP) sensor con-
nector.
4. Remove the TP sensor retaining bolts and the TP
sensor.
Installation Procedure
1. With the throttle valve closed, position the TP sen-
sor on the throttle shaft. Align the TP sensor with
the bolt holes.
2. Install the TP sensor retaining bolts.
Tighten
Tighten the throttle position sensor retaining bolts to
2 NSm (18 lb–in).
3. Connect the TP sensor connector.
4. Install the air intake tube and resonator.
5. Connect the negative battery cable.
THROTTLE BODY (1.4L/1.6L DOHC)
Removal Procedure
1. Disconnect the negative battery cable.
2. Remove the intake air tube.
3. Disconnect the breather hose.

1F – 604IENGINE CONTROLS
DAEWOO V–121 BL4
4. Disconnect the coolant hose from the throttle body.
5. Disconnect the throttle cables by opening the re-
lease slot.
6. Disconnect the main throttle idle actuator (MTIA)
electrical connector.
7. Remove the throttle body bolt and the nuts.
8. Remove the throttle body.
Installation Procedure
1. Install the throttle body assembly to the intake man-
ifold.
2. Install the throttle body retaining nuts and the bolt.
Tighten
Tighten the throttle body retaining nuts and the bolt to
15 NSm (11 lb–ft).
3. Connect the throttle cable.
4. Connect the coolant hoses.
5. Connect the breather hose.
6. Install the intake air tube.
7. Connect the negative battery cable.
THROTTLE BODY (1.8L DOHC)
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the intake air temperature (IAT) sensor
connector.
3. Disconnect the breather hose from the valve cover.
4. Remove the air intake tube.

ENGINE CONTROLS 1F – 605
DAEWOO V–121 BL4
5. Disconnect the throttle cables by opening the
throttle and moving the cable through the release
slot.
6. Disconnect the vacuum hoses from the throttle
body.
7. Disconnect the throttle position (TP) sensor and the
idle air control valve connectors.
8. Disconnect the coolant hoses from the throttle
body.
9. Remove the throttle body retaining nuts.
Notice : Cover the opening of the intake manifold after re-
moving the throttle body assembly. This will prevent any
objects or debris from entering the engine which may
cause damage.
10. Remove the throttle body and discard the gasket.
11. Remove the TP sensor. Refer to ”Throttle Position
Sensor ”in this section.
12. Remove the idle air control (IAC) valve. Refer to
”Idle Air Control Valve ”in this section.
Installation Procedure
Notice : Use care in cleaning old gasket material from ma-
chined aluminum surfaces. Sharp tools may damage seal-
ing surfaces.
1. Clean the gasket mating surface on the intake man-
ifold.
Notice : The throttle body may be cleaned in a cold immer-
sion–type cleaner following disassembly. The TP sensor
and the idle air control valve should not come in contact
with any solvent or cleaner, as they may be damaged.
2. Clean the throttle body.
3. Install the TP sensor. Refer to ” Throttle Position
Sensor ”in this section.
4. Install the IAC valve. Refer to ”Idle Air Control Valve
” in this section.
5. Install the throttle body assembly with a new gasket
to the intake manifold.
6. Install the throttle body retaining nuts.
Tighten
Tighten the throttle body retaining nuts to 10 NSm (89
lb–in).

1F – 606IENGINE CONTROLS
DAEWOO V–121 BL4
7. Connect the TP sensor connector and the IAC
valve connector.
8. Connect the coolant hoses to the throttle body.
9. Connect the vacuum hoses to the throttle body.
Important : Make sure the throttle/cruise control cables
do not hold the throttle open. With the engine off, check to
see that the accelerator pedal is free.
10. Connect the throttle cable.
11. Install the air intake tube.
12. Connect the breather hose to the valve cover.
13. Connect the IAT sensor connector.
14. Connect the negative battery cable.
15. Fill the cooling system.
FRONT HEATED OXYGEN SENSOR
(HO2S1) (1.4L/1.6L DOHC)
Removal Procedure
1. Disconnect the negative battery cable.
Notice : The oxygen sensor uses a permanently attached
pigtail and connector. This pigtail should not be removed
from the oxygen sensor. Damage or removal of the pigtail
or the connector could affect proper operation of the oxy-
gen sensor. Take care when handling the oxygen sensor.
Do not drop the oxygen sensor.
2. Disconnect the front heated oxygen sensor
(HO2S1) connector.
Notice : The oxygen sensor may be difficult to remove
when engine temperature is below 48°C (120°F). Exces-
sive force may damage threads in the exhaust manifold.
3. Carefully remove the HO2S1 from the exhaust
manifold.
Installation Procedure
Important : A special anti–seize compound is used on the
oxygen sensor threads. This compound consists of a liq-
uid graphite and glass beads. The graphite will burn away,
but the glass beads will remain, making the sensor easier
to remove. New or service sensors will already have the
compound applied to the threads. If a sensor is removed
from any engine and if for any reason it is to be reinstalled,
the threads must have anti–seize compound applied be-
fore reinstallation.
1. Coat the threads of the HO2S1 with an anti–seize
compound, if needed.
2. Install the HO2S1 into the exhaust manifold.
Tighten
Tighten the oxygen sensor to 42 NSm (31 lb–ft).
3. Connect the HO2S1 connector.
4. Connect the negative battery cable.