2003 HONDA CIVIC engine coolant

40. Install the air cleaner housinq.
6x1.0mm12 N m (1.2 kgf.m,8.7 lbt.ft)
Install the air cleaner housing cover (A) and
connect the intake air temperature (lAT) sensor
connector (B),
42. Installthe breather hose (C) and vacuum hose 1D).
41.
43. Installthe intake manifold cover.
6x1.0mm12Nm11.2kgf.m.8.7 tbf.ft)
Installthe battery. Clean the battery posts and
cable terminals with sandpaper, then assemble
them and apply grease to prevent corrosion.
Check that the transmission shifts into gear
smoothly.
Inspect for fuel leaks. Turn the ignition switch ON(ll) {do not operate the starter) so that the fuel pump
runs for about 2 seconds and pressurizes the fuel
line. Repeat this operation two or three times, then
check for fuel leakage at any point in the fuel line.
Refillthe engine with engine oil (see page 8-5).
Refill the transmission with fluid (see page 13-3).
Refill the radiator with engine coolant, and bleed
air from the cooling system with the heater valve
open (see page 10-6).
Perform the engine control module (ECM) idle learnprocedure (see page 11-139).
Inspect the idle speed (see page 1 1-138).
Inspect the ignition timing (see page 4-17).
Check the wheel alignment {see page 18-4).
Enter the anti-theft code for the radio, then enter
the customer's radio station presets.
Set the clock.
YE
44.
41.
]tE
46.
48.
49.
52.
53.
54.
50.
51.
55.
5-15

Gylinder Head Removal
NOTE:. Use fender covers to avoid damaging painted
surfaces.
To avoid damage, unplug the wiring connectors
carefully whlle holding the connector portion.
To avoid damaging the cylinder head, wait until the
engine coolant temperature drops below 100'F (38"C)
betore loosening the cylinder head bolts.
Mark all wiring and hoses to avoid misconnection.
Also, be sure that they do not contact other wiring or
hoses, or interfere with other parts.
'1.
2.
3.
Drain the engine coolant (see page 10-6).
Remove the drive belt (see page 4-26).
Remove the intake manifold {see page 9-3).
Remove the air cleaner housing (see step 7 on page
5-2t.
5. Remove the water bypass hose (A).
Remove the exhaust manifold (see page 9-7
Remove the cam chain (see page 6-12).
6.
7.
).
8. Remove the engine wire harness connectors and
wire harness clamps from the cylinder head.
. Engine coolant temperature (ECT) sensor
conneclor. Camshaft position (Cl\4P) (top dead center (TDC))
sensor B connector. Camshaft posilion (CMP) sensor A connector
9. Remove the upper radiator hose (A) and heater
hose (B).
'10. Remove the harness holder (A)from the bracket,
then remove the connecting pipe mounting boh {B)
and brake booster vacuum line mounting bolts {C).
(cont'd)
1 1. Remove the water bvpass hose (D).
6-23

14. Installthe water bvpass hose.
15. Installthe air cleaner housing (see step 37 on page
5-15).
16. Installthe intake manifold (see page 9-5).
17. Installthe exhaust manifold (see page 9-7).
'18. Installthe cam chain (see page 6-15).
19. Adjust the valve clearance (seepage6-9).
20. Installthe drive belt (see page 4-26).
21. Clean the battery posts and cable terminals with
sandpaper, then assemble them and apply grease
to prevent corrosion.
22. After installation, checkthatall tubes, hosesand
connectors are installed correctly.
23. Inspectforfuel leaks. Turn the ignition switch ON
{ll) {do not operate the starter) so that the fuel pump
runs for about 2 seconds and pressurizes the fuel
line. Repeat thls operation two or three times, then
check for fuel leakage at any point in the fuel line.
24. Refillthe radiator with engine coolant, and bleed
air from the cooling system with the heater valve
open (see page 10-6).
25. Inspect the idle speed (see page 11-'138).
26. Inspect the ignition timing (see page 4-17).
Gylinder Head Cover lnstallation
1. Thoroughly clean the head cover gasket and the
groove.
2. Installthe head cover gasket (A) in the groove of
the cylinder head cover (B).
Check that the mating surfaces are clean and dry.
Apply liquid gasket. P/N 08718-0009, on the chain
case and the No.5 rocker shaft holder mating areas.
NOTE: Do not install the parts if 5 minutes or more
have elapsed since applying liquid gasket. Instead,
reapply liquid gasket after removing old residue.
(cont'd)
6-41

Intake Manifold and Exhaust System
Intake Manifold Removal and Installation (cont'dl
5. Be prepared to catch and clean up spilled coolant.
Remove the water bypass hoses, then plug the
water bypass hoses.
6. Relievefuel pressure (see page 11-'144).
7. Remove the fuel line (seepagell-149).
8. Remove the positive crankcase ventilation (PCV)
hose (A), harness holder mounting bolt (B) and
harness clamp mounting bolt (C).
9-4
\-
(
9.Remove the engine wire harness connectors and
wire harness clamps from the intake manifold.
. Four injector connectors. ldle air control (lAC) valve connector. Throttle position (TP) sensor connector. fvlanifold absolute pressure {lvlAP) sensor
connector. Evaporative emission (EVAP)canister purge
valve connector
Remove the bolt securing the intake manifold and
bracket.
'1 0.
11.Remove allthe intake manifold mounting bolts/
nuts.
Remove the two stud bolts (A), then remove the
intake manifold (B).
1'>

lntake Manifold and Exhaust System
Intake Manifold Removal and Installation (cont'd)
9. lnstallthe air cleaner housing cover (A), and
connect the IAT sensor connector (B).
BC
Installthe breather hose (C).
lnstallthe EVAP canister hose (A), brake booster
vacuum hose (B), and vacuum hoses {C).
10.
11.
9-6
\
12. Installthe intake manifold cover.
6x1.0mm12 N.ml.1.2k91.m,8.7 tbf.ftl
Clean up any spilled engine coolant.
After installation, check that all tubes, hoses, and
connectors are installed correctly.
Inspect for fuel leaks. Turn the ignition switch ON
(ll) (do not operate the starter) so that the fuel pump
runs for about 2 seconds and pressurizes the fuel
line. Repeat this operation two or three times, then
check for fuel leakage at any point in the fuel line.
Refill the radiator with engine coolant, and bleed
air from the cooling system with the heater valve
open (see page 10-6).
to.
\-

Engine Cooling
Cooling System
Component Location Index ......................................... 10-2
Radiator Cap Test ..................... .......... 10-3
RadiatorTest ............. 10-3
Fan Motor Test .......... l0-4
Thermostat Test ...................... ........... 10-4
Water Pump Inspection ..................... 10-5
Water Pump Replacement ................. 10-5
Coolant Check .............. ....................... 10-6
Coolant Replacement ......................... 10-6
Thermostat Replacement .................. 10-8
Water Passage Installation ................ 10-9
Water Outlet Installation .................... 10-9
Radiator and Fan Replacement ................................... 10-10
Fan Controls
Component Location Index ......................................... 10-11
Symptom Troubleshooting Index ............................... 10-12
Circuit Diagram ......... 10-13
Radiator Fan CircuitTroubleshooting ........................ 10-14
Radiator Fan Switch Circuit Troubleshooting
(Open) ............ ........ 10-16
Radiator Fan Switch Circuit Troubleshooting
(Short) ............ ........ 10-16
Radiator Fan Switch Test ................... 10-17
Radiator Fan Switch Reolacement .............................. 10-17

Radiator Cap Test
1. Remove the radiator cap {A), wet its seal with
engine coolant, then install it on the pressure tester(B) (commercially available).
Apply a pressure of 93 '123 kPa {0.95 1.25
kgf/cm', l4 18 psi).
Check for a drop in pressure.
lf the pressure drops, replace the cap.
3.
4.
Radiator Test
Wait untilthe engine is cool, then carefully remove
the radiator cap and fill the radiator with engine
coolant to the top of the filler neck.
Attach the pressure tester (A) (commercially
available) to the radiator.
1.
3.
4.
Apply a pressure ot 93 '123 kPa (0.95 1 .25
kgf/cm', '14 18 psi).
Inspect for engine coolant leaks and a drop in
pressu re.
Remove the tester, and reinstall the radiator cap.
10-3

1.
2.
Water Pump Inspection
Remove the drive belt (see page 4-26),
Turn the water pump pulley counterclockwise.
Check that it turns freely.
Check for signs of seal leakage. A small amount of"weeping" from the bleed holes (A) is normal.
Water Pump Replacement
1. Remove the drive belt (see page 4-26).
2. Drain the engine coolant {see page 10-6).
3. Remove the crankshaft pulley (see page 6-11).
4. Remove the six bolts securing the water pump,
then remove the water pump (A).
6x1.0mm12 N m {1.2 kgt m,8.7 rbf.ft)
Inspect and clean the O-ring groove and mating
surface with the water passage.
Installthe water pump with new O rings in the
reverse order of removal.
7. Clean up any spilled engine coolant.
8. Installthe crankshaft pulley (see page 6-12).
L Refill the radiator with engine coolant, and bleed
air from the cooling system with the heater valve
open {see page 10-6}.
10-5