
1.8L DOHC ENGINE MECHANICAL 1C2 – 37
DAEWOO V–121 BL4
ENGINE MOUNT
Tools Required
J–28467–B Engine Assembly Support Fixture
X–28467–560 Engine Assembly Support Channel
Removal Procedure
1. Disconnect the negative battery cable.
2. Support the engine assembly using the engine as-
sembly support fixture J–28467–B, and the engine
assembly support channel X–28467–560.
3. Disconnect the manifold air temperature (MAT)
sensor connector.
4. Disconnect the air cleaner outlet hose from the
throttle body.
5. Remove the air cleaner housing bolts.
6. Remove the air cleaner housing.
7. Remove the right front splash shield. Refer to Sec-
tion 9R, Body Font End.
8. Remove the engine mount bracket retaining bolts.
9. Remove the engine mount bracket.
10. Remove the serpentine accessory drive belt. Refer
to Section 6B, Power Steering Pump.
11. Remove the front timing belt cover bolts.
12. Align the crankshaft pulley timing mark with the
pointer, and the camshaft gears with the timing
marks on the rear cover, by turning the crankshaft
gear bolt.
13. Loosen the timing belt automatic tensioner bolt.
14. Turn the hex–key tab to relieve belt tension.
15. Remove the timing belt idler pulley bolt and nut.
16. Remove the timing belt idler pulley.
17. Remove the engine mount retaining bolts.
18. Remove the engine mount.
Installation Procedure
1. Install the engine mount.
2. Install the engine mount retaining bolts.
Tighten
Tighten the engine mount retaining bolts to 45 NSm
(33 lb–ft).

1C2 – 38I1.8L DOHC ENGINE MECHANICAL
DAEWOO V–121 BL4
3. Install the timing belt idler pulleys.
4. Install the timing belt idler pulley bolt and nut.
Tighten
Tighten the timing belt idler pulley bolt and nut to 25
NSm (18 lb–ft).
5. Tension the timing belt by turning the timing belt
automatic tensioner hex–key tab counterclockwise
until the pointer is aligned to the indicator.
Tighten
Tighten the timing belt automatic tensioner bolt to 25
NSm (18 lb–ft).
6. Install the front timing belt cover.
7. Install the front timing belt cover bolts.
Tighten
Tighten the front timing belt cover bolts to 6 NSm (53
lb–in).
8. Install the engine mount bracket and retaining bolts.
Tighten
Tighten the engine mount bracket retaining bolts to 55
NSm (41 lb–ft).
9. Remove the engine assembly support fixture
J–28467–B, and the channel X–28467–560.
10. Install the serpentine accessory drive belt. Refer to
Section 6B, Power Steering Pump.
11. Connect the negative battery cable.
INTAKE MANIFOLD
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 cable.
4. Disconnect the charcoal canister purge (CCP) and
exhaust gas recirculation (EGR) solenoid from the
intake manifold and loosen the bracket bolt.
5. Drain the engine coolant. Refer to Section 1D, En-
gine Cooling.
6. Disconnect the manifold air temperature sensor
(MAT) connector.
7. Disconnect the air cleaner outlet hose from the
throttle body.

1C2 – 46I1.8L DOHC ENGINE MECHANICAL
DAEWOO V–121 BL4
7. Install the timing belt automatic tensioner and bolt.
8. Install the camshaft gears. Refer to ”Camshaft
Gears” in this section.
9. Install the timing belt and timing belt cover. Refer to
”Timing Belt” in this section.
10. Connect the negative battery cable.
ENGINE
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. Remove the hood. Refer to Section 9R, Body Front
End.
4. Drain the engine oil.
5. Disconnect the negative battery cable.
6. Discharge the air conditioning (A/C) system, if
equipped. Refer to Section 7B, Manual Control
Heating, Ventilation, and Air Conditioning Systems.
7. Disconnect the manifold air temperature (MAT)
sensor connector.
8. Remove the air cleaner outlet hose from the throttle
body and air cleaner housing.
9. Disconnect the breather tubes from the camshaft
cover.
10. Remove the right front wheel. Refer to Section 2E,
Tires and Wheels.
11. Remove the right front wheel well splash shield.
Refer to Section 9R, Body Font End.
12. Remove the serpentine accessory drive belt. Refer
to Section 6B, Power Steering Pump.
13. Drain the engine coolant. Refer to Section 1D, En-
gine Cooling.
14. Remove the cooling system radiator and the engine
cooling fans. Refer to Section 1D, Engine Cooling.
15. Disconnect the upper radiator hose from the ther-
mostat housing.
16. Disconnect the power steering return hose from the
power steering pump.
17. Disconnect the power steering pressure hose from
the power steering pump.
18. Disconnect the electrical connector at the direct
ignition system (DIS) coil and the electronic control
module (ECM) ground terminal and at the starter
motor.

1C2 – 50I1.8L DOHC ENGINE MECHANICAL
DAEWOO V–121 BL4
18. Install the exhaust flex pipe retaining nuts to the
catalytic converter or the connecting pipe.
Tighten
Tighten the exhaust flex pipe–to–catalytic converter
or connecting pipe retaining nuts to 35 NSm (26 lb–ft).
19. Connect the power steering pressure hose.
20. Connect the power steering return hose.
21. Install the A/C compressor, if equipped. Refer to
Section 7B, Manual Control Heating, Ventilation,
and Air Conditioning System.
22. Install the serpentine accessory drive belt. Refer to
Section 6B, Power Steering Pump.
23. Install the right front wheel well splash shield.
24. Install the right front wheel. Refer to Section 2E,
Tires and Wheels.
25. Connect the fuel feed line to the fuel rail.
26. Connect the fuel return line to fuel rail.
27. Install the fuel rail and injector channel cover as an
assembly. Refer to Section 1F, Engine Controls.
28. Connect all of the necessary vacuum lines including
the brake booster vacuum hose.
29. Connect the O2 sensor connector, if equipped.
30. Connect the starter solenoid ”S” terminal wire and
power lead.
31. Connect the generator voltage regulator connector.
32. Connect the CTS connector.
33. Connect the engine CTS connector.
34. Connect the TPS connector.
35. Connect the IAC valve connector.
36. Connect the MAP sensor connector.
37. Connect the knock sensor, if necessary
38. Connect the electrical connector at the DIS ignition
coil and the ECM ground terminal and at the starter
motor.
39. Install the air cleaner outlet hose between the
throttle body and the air cleaner housing.
40. Connect the breather tubes to the camshaft cover.
41. Connect the MAT sensor connector.
42. Install the cooling system radiator and the engine
cooling fans. Refer to Section 1D, Engine Cooling.

1.8L DOHC ENGINE MECHANICAL 1C2 – 61
DAEWOO V–121 BL4
4. Inspect the dimension for the valve seat width.
S Intake: 1.2 to 1.4 mm (0.047 to 0.055 inch).
S Exhaust: 1.4 to 1.8 mm (0.055 to 0.070 inch).
5. Inspect the assembly height of the intake valves
and the exhaust valves. If the dimension is exceed-
ed, install new valves. Inspect the assembly height
of the intake valves and the exhaust valves again. If
the valve assembly height is still too large despite
replacing the valves, replace the cylinder head.
Assembly Procedure
1. Coat the valve stems with engine oil.
2. Insert the valves in the cylinder head in their origi-
nal positions.
3. Insert the valve spring seats.
4. Push the accompanying assembly sleeve onto the
valve stem.
5. Insert the new valve stem seat.
6. Carefully drive the valve stem seal onto the stop
with light taps.
7. Install the valve springs in their original positions.
8. Install the valve spring caps.
9. Compress the valve springs with the valve spring
compressor KM–348 and adapter KM–653.
10. Install the valve keys.
11. Remove the valve spring compressor KM–348 and
adapter KM–653.
12. Lubricate the valve tappet adjusters with engine oil.
13. Install the valve tappet adjusters.

ENGINE COOLING 1D – 3
DAEWOO V–121 BL4
DIAGNOSIS
THERMOSTAT TEST
1. Remove the thermostat from the vehicle. Refer to
”Thermostat” in this section.
2. Make sure the valve spring is tight when the ther-
mostat is fully closed. If the spring is not tight, re-
place the thermostat.
3. Suspend the thermostat and a thermometer in a
pan of 50/50 mixture of ethylene glycol and water.
Do not let the thermostat or the thermometer rest
on the bottom of the pan because the uneven con-
centration of heat on the bottom could result in in-
accurate temperature measurements.
4. Heat the pan on a burner.
5. Use the thermometer to measure the temperature
of the heated solution.
6. The thermostat should begin to open at 87°C
(189°F) and it should be fully open at 102°C
(216°F). If it does not open at these temperatures,
replace the thermostat.
SURGE TANK CAP TEST
Tools Required
KM–471 Adapter
The surge tank cap maintains proper pressure, protects
the system from high pressure by opening a pressure
valve, and protects the coolant hoses from collapsing be-
cause of a vacuum.1. Wash any sludge from the surge tank cap and the
valve seat of the vacuum pressure valve for the
surge tank cap.
2. Check for any damage or deformity to the vacuum
pressure valve for the surge tank cap. If any dam-
age or deformity is found, replace the cap.
3. Install a suitable cooling system pressure tester to
the cap using the adapter KM–471.
4. Pull the vacuum pressure valve open. If the surge
tank cap does not seal properly, replace the surge
tank cap.
5. Pressurize the cap to 90 to 120 kPa (13.1 to 17.4
psi).
6. Wait 10 seconds and check the pressure held by
the tank cap tester.
7. If the pressure held by the cooling system pressure
tester falls below 80 kPa (11.6 psi), replace the
surge tank cap.

ENGINE COOLING 1D – 19
DAEWOO V–121 BL4
ELECTRIC COOLING FAN
CAUTION : Keep hands, tools, and clothing away
from the engine cooling fans to help prevent personal
injury. This fan is electric and can turn ON whether or
not the engine is running.
CAUTION : If a fan blade is bent or damaged in any
way, no attempt should be made to repair or reuse the
damaged part. A bent or damaged fan assembly
should always be replaced with a new one. Failure to
do so can result in personal injury.
The cooling fans are mounted behind the radiator in the
engine compartment. The electric cooling fans increase
the flow of air across the radiator fins and across the con-
denser on air condition (A/C)–equipped vehicles. This
helps to speed cooling when the vehicle is at idle or moving
at low speeds.
1.4L DOHC engine fan size is 340mm (13.4 in.) and
1.6L/1.8L DOHC engine main fan size is 300 mm (11.8
inches) in diameter with five blades to aid the air flow
through the radiator and the condenser. An electric motor
attached to the radiator support drives the fan.
A/C models have two fans – the main fan and the auxiliary
fan. The auxiliary fan is 300 mm (11.8 inches) in diameter.
Non–A/C models have only the main fan.
A/C OFF or Non–A/C Model (1.4L/1.6L)
S The cooling fans are actuated by the electronic
control module (ECM) using a low–speed cooling
fan relay and a high–speed cooling fan relay. On
A/C–equipped vehicles, a series/parallel cooling fan
relay is also used.
S The ECM will turn the cooling fans on at low speed
when the coolant temperature reaches 97.5°C
(207.5°F) and the cooling fans off at 95.25°C
(203.4°F).
A/C OFF or Non–A/C Model (1.8L)
S The cooling fans are actuated by the electronic
control module (ECM) using a low–speed cooling
fan relay and a high–speed cooling fan relay. On
A/C–equipped vehicles, a series/parallel cooling fan
relay is also used.
S The ECM will turn the cooling fans on at low speed
when the coolant temperature reaches 93°C
(199°F) and the cooling fans off at 90°C (194°F).
A/C ON (1.4L/1.6L)
S The ECM will turn the cooling fans on at low speed
when the A/C system is on. The ECM will change
to high speed when the coolant temperature reach-
es 101.25°C (214°F) or the high side A/C pressure
reaches 1859 kPa (270 psi).
S The cooling fans will return to low speed when the
coolant temperature reaches 99°C (210°F) and the
high side A/C pressure reaches 1449 kPa (210 psi).
A/C ON (1.8L)
S The ECM will turn the cooling fans on at low speed
when the A/C system is on. The ECM will change
to high speed when the coolant temperature reach-
es 97°C (207°F) or the high side A/C pressure
reaches 1859 kPa (270 psi).
S The cooling fans will return to low speed when the
coolant temperature reaches 94°C (201°F) and the
high side A/C pressure reaches 1449 kPa (210 psi).
ENGINE BLOCK HEATER
The vehicle is designed to accept an engine block heater
that helps to warm the engine and to improve starting in
cold weather. It also can help to reduce fuel consumption
while a cold engine warms up.
The engine block heater is located under the intake man-
ifold and uses an existing expansion plug for installation.

1E – 10IENGINE ELECTRICAL
DAEWOO V–121 BL4
GENRATOR OUTPUT TEST
1. Perform the generator system test. Refer to ”Gen-
erator System Check”in this section.
2. Replace the generator if it fails that test. Refer to
”Generator” in the On–Vehicle Service portion of
this section. If it passes the test, perform the on–
vehicle output check which follows.
Important : Always check the generator for output before
assuming that a grounded ”L” terminal circuit has dam-
aged the regulator.
3. Attach a digital multimeter, an ammeter, and a car-
bon pile load to the vehicle.
Important : Be sure the vehicle battery is fully charged,
and the carbon pile load is turned off.
4. With the ignition switch in the OFF position, check
and record the battery voltage.
5. Remove the harness connector from the generator.
6. Turn the ignition to RUN with the engine not run-
ning. Use a digital multimeter to check for voltage in
the harness connector ”L” terminal.
7. The reading should be near the specified battery
voltage of 12 volts. If the voltage is too low, check
the indicator L" terminal circuits for open and
grounded circuits causing voltage loss. Correct any
open wires, terminal connections, etc., as neces-
sary. Refer to”Charging System” in this section.
8. Attach the generator harness connector.
9. Run the engine at a moderate idle, and measure
the voltage across the battery terminals. The read-
ing should be above that recorded in step 14, but
less than 16 volts. If the reading is over 16 volts or
below the previous reading, replace the generator.
Refer to”Generator” in the On–Vehicle Service sec-
tion.
10. Run the engine at a moderate idle, and measure
the generator amperage output.
11. Turn on the carbon pile, and adjust it to obtain the
maximum amps while maintaining the battery volt-
age above 13 volts.
12. If the reading is within 15 amps of the generator’s
rating noted on the generator, the generator is
good. If not, replace the generator. Refer to”Gener-
ator” in the On–Vehicle Service section.
13. With the generator operating at the maximum out-
put, measure the voltage between the generator
housing and the battery negative terminal. The volt-
age drop should be 0.5 volt or less. If the voltage
drop is more than 0.5 volt, check the ground path
from the generator housing to the negative battery
cable.
14. Check, clean, tighten, and recheck all of the ground
connections.
GENERATOR SYSTEM CHECK
When operating normally, the generator indicator lamp will
come on when the ignition is in RUN position and go out
when the engine starts. If the lamp operates abnormally
or if an undercharged or overcharged battery condition oc-
curs, the following procedure may be used to diagnose the
charging system. Remember that an undercharged bat-
tery is often caused by accessories being left on overnight
or by a defective switch that allows a lamp, such as a trunk
or a glove box lamp, to stay on.
Diagnose the generator with the following procedure:
1. Visually check the belt and the wiring.
2. With the ignition in the ON position and the engine
stopped, the charge indicator lamp should be on. If
not, detach the harness at the generator and
ground the ”L” terminal in the harness with a 5–am-
pere jumper lead.
S If the lamp lights, replace the generator. Refer to
”Generator” in the On–Vehicle Service section.
S If the lamp does not light, locate the open circuit
between the ignition switch and the harness
connector. The indicator lamp bulb may be
burned out.
3. With the ignition switch in the ON position and the
engine running at moderate speed, the charge indi-
cator lamp should be off. If not, detach the wiring
harness at the generator.
S If the lamp goes off, replace the generator. Re-
fer to ”Generator” in the On–Vehicle Service
section.
S If the lamp stays on, check for a short to ground
in the harness between the connector and the
indicator lamp.
Important : Always check the generator for output before
assuming that a grounded ”L” terminal circuit has dam-
aged the regulator. Refer to”Generator” in the Unit Repair
section.