Oxygen sensor DAEWOO NUBIRA 2004 Service Repair Manual

1C1 – 12I1.4L/1.6L DOHC ENGINE MECHANICAL
DAEWOO V–121 BL4
INTAKE & EXHAUST MANIFOLD
1. Oxygen Sensor
2. Heat Shield
3. Exhaust Manifold
4. Exhaust Manifold Gasket
5. Intake Manifold
6. Main Throttle Idle Actuator (MTIA) Gasket
7. MTIA
8. Clamp9. Intake Air Tube
10. Breethe Hose
11. Aircleaner Assembly
12. Aircleaner Upper Hosing
13. Aircleaner Eliment
14. Aircleaner Lower Housing
15. Resoinator
16. Air Intet Hose

1C1 – 20I1.4L/1.6L DOHC ENGINE MECHANICAL
DAEWOO V–121 BL4
12. Install the throttle body and engine cover.
13. Refill the engine cooling system. Refer to Section
1D, Engine Cooling.
14. Install the fuel pump fuse and connect the negative
battery cable.
EXHAUST MANIFOLD
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the oxygen sensor connecter.
3. Remove the exhaust manifold heat shield.
4. Remove the exhaust manifold nuts from the pup
converter.
5. Remove the exhaust manifold retaining nuts in the
sequence shown and remove the exhaust manifold.
6. Remove the exhaust manifold gasket.
7. Clean the sealing surfaces of the exhaust manifold
and the cylinder head.

1.4L/1.6L DOHC ENGINE MECHANICAL 1C1 – 21
DAEWOO V–121 BL4
Installation Procedure
1. Install the exhaust manifold and gasket.
2. Install the exhaust manifold retaining nuts and tight-
en in the sequence shown.
Tighten
Tighten the exhaust manifold retaining nuts to 25 NSm
(18 lb–ft).
3. Install the exhaust manifold nuts to the catalytic
converter.
Tighten
Tighten the exhaust manifold nuts to 40 NSm (30 lb–
ft).
4. Install the heat shield.
Tighten
Tighten the the heat shield bolts to 13 NSm (10 lb–ft).
5. Connect the oxygen sensor connecter.
6. Connect the negative battery cable.
CYLINDER HEAD AND GASKET
Tools Required
J–42492 Timing Belt Adjuster
KM–470–B Angular Torque Gauge
Removal Procedure
1. Remove the fuel pump fuse.
2. Start the engine. After it stalls, crank the engine for
10 seconds to rid the fuel system of fuel pressure.
3. Disconnect the negative battery calbe.
4. Disconnect the electronic control module(ECM)
ground terminal from the intake manifold.
5. Drain the engine coolant. Refer to Section 1D, En-
gine Cooling.

1.4L/1.6L DOHC ENGINE MECHANICAL 1C1 – 29
DAEWOO V–121 BL4
38. Connect the DIS coil connector.
39. Connect the fuel injector harness connectors.
40. Connect the oxygen sensor connector and the
ECM ground terminal at the intake manifold.
41. Install the fuel pump fuse.
42. Connect the negative battery ground cable.
43. Refill the engine cooling system. Refer to Sec-
tion1D, Engine Cooling.
CAMSHAFTS
Removal Procedure
1. Remove the camshaft cover. Refer to ”Camshaft
Cover” in this section.
2. Remove the timing belt. Refer to ”Timing Belt” in
this section.
Notice : Take extreme care to prevent any scratches,
nicks or damage to the camshafts.
3. While holding the intake camshaft firmly in place,
remove the intake camshaft gear bolt and gear.
4. While holding the exhaust camshaft firmly in place,
remove the exhaust camshaft gear bolt and gear.
5. Remove the camshaft cap bolts gradually in the
sequence shown for each camshaft cap.

1.4L/1.6L DOHC ENGINE MECHANICAL 1C1 – 49
DAEWOO V–121 BL4
17. Disconnect the oxygen (O2) sensor connector, if
equipped.
18. Disconnect the fuel injector harness connectors.
19. Disconnect the MAT, MAP sensor connectors.
20. Disconnect the throttle position sensor (TPS) con-
nector.
21. Disconnect the generator voltage regulator connec-
tor and power lead.
22. Remove the electrical harness clamp bolt.
23. Disconnect all of the necessary vacuum lines, in-
cluding the brake booster vacuum hose.
24. Disconnect the fuel feed line at the fuel rail.
25. Disconnect the throttle cable from the throttle body
and the intake manifold bracket.
26. Disconnect the surge tank coolant hose at the
throttle body.
27. Disconnect the heater outlet hose at the coolant
pipe.
28. Disconnect the heater inlet hose from the cylinder
head.
29. Disconnect the surge tank coolant hose from the
coolant pipe.
30. Disconnect the lower radiator hose from the coolant
pipe. Disconnect the starter solenoid ”S” terminal
wire. Remove the A/C compressor, if equipped. Re-
fer to Section 7B, Manual Control Heating, Ventila-
tion, and Air Conditioning Systems.
31. Remove the catalytic converter retaining nuts from
the exhaust pipe.
32. Remove the exhaust pipe.

1.4L/1.6L DOHC ENGINE MECHANICAL 1C1 – 77
DAEWOO V–121 BL4
GENERAL DESCRIPTION
AND SYSTEM OPERATION
CYLINDER HEAD AND GASKET
The cylinder head is made of an aluminum alloy. The cylin-
der head uses cross–flow intake and exhaust ports. A
spark plug is located in the center of each combustion
chamber. The cylinder head houses the dual camshafts.
CRANKSHAFT
The crankshaft has eight integral weights which are cast
with it for balancing. Oil holes run through the center of the
crankshaft to supply oil to the connecting rods, the bear-
ings, the pistons, and the other components. The end
thrust load is taken by the thrust washers installed at the
center journal.
TIMING BELT
The timing belt coordinates the crankshaft and the dual
overhead camshafts and keeps them synchronized. The
timing belt also turns the water pump. The timing belt and
the pulleys are toothed so that there is no slippage be-
tween them. There are two idler pulleys. An automatic ten-
sioner pulley maintains the timing belt’s correct tension.
The timing belt is made of a tough reinforced rubber similar
to that used on the serpentine accessory drive belt. The
timing belt requires no lubrication.
OIL PUMP
The oil pump draws engine oil from the oil pan and feeds
it under pressure to the various parts of the engine. An oil
strainer is mounted before the inlet of the oil pump to re-
move impurities which could clog or damage the oil pump
or other engine components. When the drive gear rotates,
the driven gear rotates. This causes the space between
the gears to constantly open and narrow, pulling oil in from
the oil pan when the space opens and pumping the oil out
to the engine as it narrows.
At high engine speeds, the oil pump supplies a much high-
er amount of oil than is required for lubrication of the en-
gine. The oil pressure regulator prevents too much oil from
entering the engine lubrication passages. During normal
oil supply, a coil spring and valve keep the bypass closed,
directing all of the oil pumped to the engine. When the
amount of oil being pumped increases, the pressure be-
comes high enough to overcome the force of the spring.This opens the valve of the oil pressure regulator, allowing
the excess oil to flow through the valve and drain back to
the oil pan.
OIL PAN
The engine oil pan is mounted to the bottom of the cylinder
block. The engine oil pan houses the crankcase and is
made of cast metal.
Engine oil is pumped from the oil pan by the oil pump. After
it passes through the oil filter, it is fed through two paths
to lubricate the cylinder block and the cylinder head. In one
path, the oil is pumped through the oil passages in the
crankshaft to the connecting rods, then to the pistons and
the cylinders. It then drains back to the oil pan. In the sec-
ond path, the oil is pumped through the oil passages to the
camshaft. The oil passes through the internal passage-
ways in the camshafts to lubricate the valve assemblies
before draining back to the oil pan.
EXHAUST MANIFOLD
A single four–port, rear–takedown manifold is used with
this engine. The manifold is designed to direct escaping
exhaust gases out of the combustion chambers with a
minimum of back pressure. The oxygen sensor is
mounted to the exhaust manifold.
INTAKE MANIFOLD
The intake manifold has four independent long ports and
uses inertial supercharging to improve engine torque at
low and moderate speeds. The plenum is attached to the
intake manifold.
CAMSHAFTS
This engine is a dual overhead camshaft (DOHC) type,
which means there are two camshafts. One camshaft op-
erates the intake valves, and the other camshaft operates
the exhaust valves. The camshafts sit in journals on the
top of the engine in the cylinder head and are held in place
by camshaft caps. The camshaft journals of the cylinder
head are drilled to create oil passages. Engine oil travels
to the camshafts under pressure where it lubricates each
camshaft journal. The oil returns to the oil pan through
drain holes in the cylinder head. The camshaft lobes are
machined into the solid camshaft to open and close the in-
take and the exhaust valves precisely the correct amount
at the correct time. The camshaft lobes are oiled by splash
action from pressurized oil escaping from the camshaft
journals.

1C2 – 14I1.8L DOHC ENGINE MECHANICAL
DAEWOO V–121 BL4
6. Disconnect the manifold air temperature (MAT)
sensor connector.
7. Disconnect the breather tube from the camshaft
cover.
8. Disconnect the air cleaner outlet hose from the
throttle body.
9. Disconnect the direct ignition system (DIS) coil con-
nector.
10. Disconnect the oxygen (O2) sensor connector, if
equipped.
11. Disconnect the idle air control (IAC) valve connec-
tor.
12. Disconnect the throttle position sensor (TPS) con-
nector.
13. Disconnect the engine coolant temperature (ECT)
sensor connector.
14. Disconnect the coolant temperature sensor (CTS)
connector.
15. Remove the air cleaner housing bolts.
16. Remove the air cleaner housing.
17. Remove the right front wheel. Refer to Section 2E,
Tires and Wheels.
18. Remove the right front wheel well splash shield.
19. Install the engine assembly support fixture
J–28467–B.
20. Remove the right engine mount bracket and bolts.
21. Disconnect the upper radiator hose at the thermo-
stat housing.
22. Remove the serpentine accessory drive belt. Refer
to Section 6B, Power Steering Pump.
23. Remove the crankshaft pulley bolts.
24. Remove the crankshaft pulley.

1.8L DOHC ENGINE MECHANICAL 1C2 – 41
DAEWOO V–121 BL4
14. Connect the MAP sensor connector.
15. Connect the coolant hoses to the throttle body.
16. Connect the IAC valve connector.
17. Connect the TPS connector.
18. Connect the air cleaner outlet hose to the throttle
body.
19. Connect the MAT sensor connector.
20. Connect the CCP and EGR solenoid at the intake
manifold and tighten the bracket bolt.
Tighten
Tighten the charcoal canister purge and exhaust gas
recirculation solenoid bracket bolt to 5 NSm (44 lb–in).
21. Install the fuel pump fuse.
22. Connect the negative battery cable.
23. Refill the engine cooling system. Refer to Section
1D, Engine Cooling.
EXHAUST MANIFOLD
Removal Procedure
1. Disconnect the negative battery cable.
2. Disconnect the oxygen (O2) sensor connector, if
equipped.
3. Remove the exhaust manifold heat shield bolts.
4. Remove the exhaust manifold heat shield.
5. Remove the exhaust flex pipe retaining nuts from
the exhaust manifold studs.

1.8L DOHC ENGINE MECHANICAL 1C2 – 47
DAEWOO V–121 BL4
19. Disconnect the oxygen (O2) sensor connector, if
equipped.
20. Disconnect the idle air control (IAC) valve connec-
tor.
21. Disconnect the throttle position sensor (TPS) con-
nector.
22. Disconnect the engine coolant temperature sensor
(CTS) connector.
23. Disconnect the CTS connector.
24. Disconnect the generator voltage regulator connec-
tor and power lead.
25. Disconnect all of the necessary vacuum lines, in-
cluding the brake booster vacuum hose.
26. Disconnect the fuel return line at the fuel rail.
27. Disconnect the fuel feed line at the fuel rail.
28. Remove the fuel rail and injector channel cover as
an assembly. Refer to Section 1F, Engine Controls.
29. Disconnect the throttle cable from the throttle body
and the intake manifold bracket.
30. Disconnect the coolant hose at the throttle body.
31. Disconnect the heater outlet hose at the coolant
pipe.
32. Disconnect the coolant bypass hose from the cylin-
der head.
33. Disconnect the surge tank coolant hose from the
coolant pipe.
34. Disconnect the lower radiator hose from the coolant
pipe.
35. Disconnect the starter solenoid ”S” terminal wire
and power lead.
36. Remove the A/C compressor. Refer to Section 7B,
Manual Control Heating, Ventilation, and Air Condi-
tioning Systems.
37. Remove the exhaust flex pipe retaining nuts from
the exhaust manifold studs.
38. Remove the exhaust flex pipe retaining nuts from
the catalytic converter or the connecting pipe.
39. Remove the exhaust flex pipe.

1.8L DOHC ENGINE MECHANICAL 1C2 – 75
DAEWOO V–121 BL4
GENERAL DESCRIPTION
AND SYSTEM OPERATION
CYLINDER HEAD AND GASKET
The cylinder head is made of an aluminum alloy. The cylin-
der head uses cross–flow intake and exhaust ports. A
spark plug is located in the center of each combustion
chamber. The cylinder head houses the dual camshafts.
CRANKSHAFT
The crankshaft has eight integral weights which are cast
with it for balancing. Oil holes run through the center of the
crankshaft to supply oil to the connecting rods, the bear-
ings, the pistons, and the other components. The end
thrust load is taken by the thrust washers installed at the
center journal.
TIMING BELT
The timing belt coordinates the crankshaft and the dual
overhead camshafts and keeps them synchronized. The
timing belt also turns the coolant pump. The timing belt
and the pulleys are toothed so that there is no slippage be-
tween them. There are two idler pulleys. An automatic ten-
sioner pulley maintains the timing belt’s correct tension.
The timing belt is made of a tough reinforced rubber similar
to that used on the serpentine drive belt. The timing belt
requires no lubrication.
OIL PUMP
The oil pump draws engine oil from the oil pan and feeds
it under pressure to the various parts of the engine. An oil
strainer is mounted before the inlet of the oil pump to re-
move impurities which could clog or damage the oil pump
or other engine components. When the crankshaft ro-
tates, the oil pump driven gear rotates. This causes the
space between the gears to constantly open and narrow,
pulling oil in from the oil pan when the space opens and
pumping the oil out to the engine as it narrows.
At high engine speeds, the oil pump supplies a much high-
er amount of oil than required for lubrication of the engine.
The oil pressure regulator prevents too much oil from en-
tering the engine lubrication passages. During normal oil
supply, a coil spring and valve keep the bypass closed, di-
recting all of the oil pumped to the engine. When the
amount of oil being pumped increases, the pressure be-
comes high enough to overcome the force of the spring.This opens the valve of the oil pressure regulator, allowing
the excess oil to flow through the valve and drain back to
the oil pan.
OIL PAN
The engine oil pan is mounted to the bottom of the cylinder
block. The engine oil pan houses the crankcase and is
made of cast aluminum.
Engine oil is pumped from the oil pan by the oil pump. After
it passes through the oil filter, it is fed through two paths
to lubricate the cylinder block and cylinder head. In one
path, the oil is pumped through oil passages in the crank-
shaft to the connecting rods, then to the pistons and cylin-
ders. It then drains back to the oil pan. In the second path,
the oil is pumped through passages to the camshaft. The
oil passes through the internal passageways in the cam-
shafts to lubricate the valve assemblies before draining
back to the oil pan.
EXHAUST MANIFOLD
A single four–port, rear–takedown manifold is used with
this engine. The manifold is designed to direct escaping
exhaust gases out of the combustion chambers with a
minimum of back pressure. The oxygen sensor is
mounted to the exhaust manifold.
INTAKE MANIFOLD
The intake manifold has four independent long ports and
utilizes an inertial supercharging effect to improve engine
torque at low and moderate speeds.
CAMSHAFTS
This engine is a dual overhead camshaft (DOHC) type,
which means there are two camshafts. One camshaft op-
erates the intake valves, and the other camshaft operates
the exhaust valves. The camshafts sit in journals on the
top of the engine (in the cylinder head) and are held in
place by camshaft caps. The camshaft journals of the cyl-
inder head are drilled for oil passages. Engine oil travels
to the camshafts under pressure where it lubricates each
camshaft journal. The oil returns to the oil pan through
drain holes in the cylinder head. The camshaft lobes are
machined into the solid camshaft to precisely open and
close the intake and the exhaust valves the correct
amount at the correct time. The camshaft lobes are oiled
by splash action from pressurized oil escaping from the
camshaft journals.