cooling system HONDA CIVIC 1996 6.G Workshop Manual

Engine
Engine Removal/lnstallation ................ 5-1
Gylinder Head/Valve Train ................... 6-1
Engine Bfock .......... ...........7-1
Engine Lubrication ........... 8-1
Intake Manifold/Exhaust System ........ 9'1
Cooling ......... 10-1

Engine Removal/lnstallation
Installation (cont'd)
Except CVT:
12 x 1.25 mm64 N.m (6.5 kgd.m,
Tighten the bolts/nut on the left front mount in thenumbered sequence shown {O - @).
(t 12 x 1.25 mm83 N'm (8.5 kgf.m,61 tbt.trl
/+4 N.m 14.5 kgf.m,33 lbt.trl
O 12 r 1.25 mm59 N.m 16.0 kgt.m,43 tbt.rtlSeplace.
5-16
\
7. Perform the following:
. Clean the areas where the driveshaft(s) and theintermediate shaft contact the transmission (dif_ferential) thoroughly with solvent or carburetorcteaner, and dry with compressed air.. Check that the set rings on the ends of the drive_shaft and intermediate shaft click into place.CAUTION: Use new set rings,. Adjust the shift cable (see section 14).. Adjust the throttle cable (see section 11).. Adjust the cruise control cable (see section 23).. Refill the engine with engine oil (see page 8-6).. Refill the transmission with fluid (see section 13,14).
. Refill the radiator with engine coolant (see page10-7).
. Bleed air from the cooling system with the heatervalve open (see page j0-7).
. Clean the battery posts and cable terminals withsandpaper, assemble them, then apply grease toprevent corrosaon.. Inspect for fuel leakage (see section j l).After assembling the fuel line, turn on l) the igni_tion switch (do not operate the starter) so that thefuel pump runs for approximately two secondsand the fuel line pressurizes. Repeat this opera_taon two or three times, then check for fuel leak_age at any point in the fuel line,

lllustrated Index
@@ system is under high pressure when theengine is hot. To avoid dangsr of rsleasing scaldingengine coolant, removo the cap only when the engine iscoot.
Total Cooling System Capacity flncluding heater andfoservoir (0.4 f (0.42 US qt, 0.35 tmp qt)ll:
*2: 81642 engine*3: D16Y7 engine*4: D16Y8 engine
CAUTION: lf any engine coolant spills on painted por-tions of the body, rinse it off immediately.
NOTE:
. Check all cooling system hoses for damage, leaks ordeterioration and replace if necessary.. Check all hose clamps and retighten if necessary.. Use new O-rings when reassembling.
RADIATOR CAPPressure test, page '10 86x1.0mm9.8 N.m {1.0 kgtm,7.2 tbt.ltl
UPPERRADIATORHOSE
UPPER BRACKETAND CUSHION
COOLANT
RAOIATOREngine coolant refilling and bleeding,page 10 7Leak test, page 10-9Inspect soldered joints andseams for leaks,Blow out dirt Irom betweencore fins with compressed air.lf insects, etc,, are cloggingradiator, wash them off withrow pressure water.
RESERVOIR
5x0.8mmA: ,1.4 N.m {0.45 kgf.m, 3.3 tbtftlg: 5.4 N.m (0.55 kgtm.4.0 tbf.ft)
6x1.0mm7.2 N.m (0.73 kgt.m,5.3 tbtftl
LOWERCUSHION
RADIATOR FANBADIATORFAN
DRAINPLUG
O-RINGReplace.
LOWEBRADIATORHOSE
FAN MOTOR SHROUD
Ar TOYO RADIATOR manufactured radiatorB: NIPPONDENSO manufacfared raoraror
10-2
Refer to section 14when installing.
Mt-|-4.2 f (4.4 US qt,3.7 tmp qt)*j
5.0 / (5.3 U$ q1, 4.4 16p q11*z
4.1 f (4.3 US qt, 3.6 lmp q0*3
4.31 (4.5 US qt, 3.8 tmp qt)*a
CVT4.3 f (4.5 US qt,3.8 Imp qt)
*1i D16Y5, D16Y7, D16Y8 engines
iil

EGT Switch
-f
Testing
Replace the thermostat if it is open at room temperature'
To test a closed thermostat:
1, Suspend the thermostat in a container of water as
shown.
THEBMOMETER
THERMOSTAT
Heat the water, and check the temperature with a
thermometer. Check the temperature at which the
thermostat first opens, and at which it is fully open
CAUTION: Do not let the thermometer touch the
bottom of the hot Gonlainel.
Measure lift height of the thermostat when fully
open.
STANDARD THERMOSTAT
Lift height above 8.0 mm (0.31 inl
Starts opsning: 169' - 176'F (76' - 80'Cl
Fully open: 194'F {90"C1
!'o
10-1 1
Testing
!!@ Romoving the EcT swhch while lhs engine
i!-ot can cause the coolant to sPray out, seriously scald-
ing you. Always lst th€ ongine and rediator cool down
before removing ihe ECT switch.
NOTE: Bleed air from the cooling system after installing
the ECT switch (see Page 10-7)
1. Remove the ECT switch from the thermostat hous-
ing (see Page'10-10).
2. Suspend the ECT switch in a container of water as
shown.
Heat the water, and check the temperature with a
thermometer.
CAUTION: Do not let the thermomoter touch tho
bottom of the hot container'
Measure the resistance between the A and B termi-
nals according to the table.4.
Terminal
Oo"rffi
swlTcH
ON196' - 203"F
(91" - 95'C)o--o
OFF
5" - 15'F {3" - 8'C)
lower than the temPera-
ture when t goes on

Diagnostic Trouble Code (DTCI Chart
connector is connecteda1: Dl6Y5 engine (CVT)*2: Except D16Y5 engine (M/T)*14:'97 model*15:'96 model*16: '98 model
(cont'd)
11-97
DTC
{MlL indication*lDelection liemProbable CausePage
Manifold Absolute
Pressure Circuit
Range/Performance Problem
. Vacuu m connection. MAP sensor11115
P0107 (3)
Manifold Absolute
Pressure Circuit
Low Input
Open or short in MAP sensor circuit
MAP sensor
ECMiPCM
TCM*1
11't1'l
P0108 (3)Manifold Absolute
Pressure Circuit
High Input
Open in MAP sensor circuit
MAP sensor
ECtvt/PCM
't 1 121
P0.111*14. *15 (10)
lntake Air Temperature
Circuit
Range/Performance Problem
. IAT sensor11-124
PO112 {10}
Intake Air
Temperature Circuit
Low Input
Short in IAT sensor circuit
IAT sensor
ECMiPCM
11-125
P0113 (10)lntake Air
Temperature Circuit
High Input
Open in IAT sensor circuit
IAT sensor
ECM/PCM
't1-126
P0116 (86)Engine Coolant
Temperature Circuit
Range/Performance Problem
. ECT sensor. Cooling system11-124
PO't't7 {6)
Engine Coolant
Temperature Circuit
Low Input
Short in ECT sensor circuit
ECT sensor
ECM/PCM
11-129
P0118 (6)Engine Coolant
Temperature Circuit
High lnput
Open in ECT sensor circuit
ECT sensor
ECM/PCM
11-130
?0122 t1l
Throttle Position
CircuitLow Input
Open or short in TP sensor circuit
TP sensorECM/PCM
TCM*1
11-132
P0123 (7)Throttle Position
Circuit
High Input
Open in TP sensor circuit
TP sensor
ECM/PClvl
11-136
P0131*' (1)
Primary Heated Oxygen Sensor
Circuit Low Voltage(Sensor 1)
Short in Primary HO2S (Sensorl ) circuit
Primary HO2S {Sensor 1)
Fuel supply system
ECM/PCM
1 1-139
P0132*' ('r)
Primary Heated Oxygen Sensor
Circuit High Voltage(Sensor 1)
Open in Primary HO2S {Sensor 1} circuit
Primary HO2S (Sensor 1)
ECM/PCM
1 1- 143
P0133*' (61)
Primary Heated Oxygen Sensor
Slow Response(Sensor 1)
. Primary HO2S (Sensorl). Exhaust system11-145
P0135*? (41)
Primary Heated Oxygen
Sensor Heater
Circuit Malfunction(Sensor 1)
. Open or short in Primary HO2S(Sensor 1) heater circuit. ECM11-151
*: The DTCS in parenthesis will be indicated by the blinking of the Malfunction Indicator Lamp (MlL) when the SCS service
! ta

3.
5.
6.
1.
Fuel Cut-off Control
. During deceleration with the throttle valve closed, current to the fuel injectors is cut off to improve fuel economy at
speeds over the following rpm:. D16Y5 engine (M/T):850 rpm. D]6Y5 engine (CVT), D'16Y8 engine (USA M/T): 920 rpm
. Dl6Y8 engine (USA A,/I), D16Y7 engine (USA A,/T);910 rpm
. D16Y8 engine (Canada M/T), D16Y7 engine (canada): 990 rpm
' D16Y8 engine (Canada M/T): 1,000 rpm
. 816A2 engine: 970 rpm
. Fuel cut-off action also takes place when engine speed exceeds 6,900 rpm (D16Y5, D16Y7 engine; D'16Y8 engine:
7,000 rpm. 816A2 engine: 8.100 rpm), regardless of the position of the throttle valve, to protect the engine from
over-rewing. With '99 Dl6Y7 engine (A,/T) and '99 D16Y8 engine (A./T), the PCM cuts the fuel at engine speeds over
5,000 rpm when the vehicle is not moving.
IVC Compressor Clutch Relay
When the ECM/PCM receives a demand for cooling from the air conditioning system, it delays the compressor from
being energized, and enriches the mixture to assure smooth transition to the A,/C mode
Evaporative Emission (EVAP) Purge Control Solenoid Valve*'
When the engine coolant temperature is above 154'F (68'C). the ECM/PCM controls the EVAP purge control solenoid
valve which controls vacuum to the EVAP purge control canister.
Evaporative Emission (EVAP) Purge Control Solenoid Valve*a
When the engine coolant temperature above 154"F (68"C), intake air temperature above 32"F (0'C) and vehicle speed
above 0 mile (0 km/h) or [Ay'C compressor clutch on and intake air temperature above 160"F (41'C)], the ECM/PCM
controls the EVAP purge control solenoid valve which controls vacuum to the EVAP purge control canister.
Exhaust Gas Recirculation (EGR) Control Solenoid Valve*?
When EGR is required for control of oxides of nitrogen (NOx) emissions. the ECM controls the EGR control solenoid
valve which supplies regulated vacuum to the EGR valve
Alternator Control
The system controls the voltage generated at the alternator in accordance with the electrical load and driving mode,
which reduces the engine load to improve the fuel economy.
ECM/PCM Fail-safe/Back-up Functions
1. Fail safe Function
When an abnormality occurs in a signal from a sensor, the ECM/PCM ignores that signal and assumes a pre-pro-
grammed value for that sensor that allows the engine to continue to run.
2. Back-uD Function
When an abnormality occurs in the ECM/PCM itself, the fuel injectors are controlled by a back-up circuit independent
of the system in order to permit minimal driving.
3. Self diagnosis Function lMalfunction Indicator Lamp (MlL)l
When an abnormality occurs in a signal from a sensor, the ECM/PCM supplies ground for the lvllL and stores the DTC
in erasable memory. When the ignition is initially turned on, the ECM/PCM supplies ground for the MIL for two sec-
onds to check the MIL bulb condition.
4. Two Trip Detection Method
To prevent false indications, the Two Trip Detection Method is used for the HO2S, fuel metering-related. idle control
system, ECT sensor, EGR system and EVAP control system self-diagnostic functions. When an abnormality occurs,
the ECM/PCM stores it in its memory. When the same abnormality recurs after the ignition switch is turned OFF and
ON 0l) again, the ECM/PCM informs the driver by lighting the MlL. However, to ease troubleshooting, this function is
cancelled when you jump the service check connector. The MIL will then blink immediately when an abnormality
occurs,
5. Two (or Three) Driving Cycle Detection Method
A "Driving Cycle" consists ot starting the engine. beginning closed loop operation, and stopping the engine. lf misfir-
ing that increases emissions is detected during two consecutive driving cycles, or TWC deterioration is detected dur-
ing three consecutive driving cycles, the ECM/PCM turns the MIL on. However, to ease troubleshooting, this function
is cancelled when you jump the service check connector. The MIL will then blink immediately when an abnormality
occurs.
(cont'd)
1 1-1 05
.1.

PGM-FI System
Engine Coolant Temperature (ECTI Sensor
The scan tool indicates Diagnostic Trouble code (DTC) P0116; A range/performance problem in the EngrneCoolant Temperature (ECT) Sensor circuit.
The ECT Sensor is a temperature dependant resistor (thermistor). The resistance of the thermistor decreases as the enginecoolant temperature increases as shown oetow.
RESISTANCE(ko)
NOTE: lf DTC P0117 and/or P01'18 are stored at the same time as DTCfor DTC P0116.
Possible Cause
. ECT sensor deterioration. Malfunction in the thermostat and cooling system
Troubleshooting Flowchart
-a 32 68 r0a la0l?6 2t2 2481'rr-20 o 20 ao o D r@ Il, r'c)
ENGINE COOLANT IEMPERATURE
P0116, troubleshoot those DTCS first. then recheck
11-128
THERMISTOR
- The MIL has bogn reported on.- DTC P0116 is stored.
Problem verification:1. Start the engine. Hotd theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator fan comes on,then let it idle.2. With the scan tool, check the
Intermiftent lailure. system is OKai thi. time. Ch.ck the thc.mo-stat 6nd thc cooling system.
is 176 200'F {80 - 93'C)or0.0-0.TVindicated?
Check the thermostat and thecooling system. ll they als OK,raplace the ECT sensor.

ldle Gontrol System
Air Gonditioning Signal ('96 - 98 Models, '99 - 00 Dl6Y5 engine with M/Tl
a {32P1ECM/PCM CONNECTORS
Wire side of female terminals
c l3lPl
This sjgnals the ECM/PCM when there is a demand for cooling from the air conditioning system.
(To page 11-205)
Check for a short in the wire{ACS line):1. Turn the ignition switch OFF.2. Disconnect the A/C pressure
switch 2P connector {see section 22).3. Turn the ignition switch ON (ll).
4. Measure vo lta ge betweenECM/PCM connector termi-nals C5 and A9.
Check for a .hort in the wi.e {ACSline):1. Turn the ignition switch OFF.2. Disconnect the ECM/PCM con-nector C (3lPi.
3. Check tor continuity betweenbody ground and ECM/PCMconnector terminal C5,
ls there approx. 5 V?
Reotir short in the wi.e betweenthe ECM/PCM lc5l and rhe A/Cpressure switch.
ls there continuity?
- Substitute a known-goodECM/rcM .nd re.fieck. f Dre-scribed voltage is now availtble, replace the original ECft4/PCM,- See the air conditioner inspe-tion ls€e s€ction 221.
Check tor an op€n in the wireIACC lin6l:1. Turn the ignition switch OFF.2. Reconnect the A/C pressure
switch 2P connector.3. Turn the ignition switch ON (ll).
4. Momentarily connect ECM/PCM connector terminals A9and A17 with a jumper wire
LGl IBRN/8LKIACS {BLU/RED)
2361I9't0Itt3a89t0
12't31al5l617t8t920232all12l3l!ai5!617'tE
252l2A2930232a252930
ACS (BLU/BEDI
LGl IBRN/BLKI
123aslslrl lolgl ro lrr I
121314l516y)nltslnl/@) zr I zr I
25271!M1 1-/r
ACC
11-204
IBLK/RED)JUMPER WIRE

ldle Control System
Air Conditioning Signal ('99 - 00 Models except Dl6Y5 engine with M/Tl
This signals the ECM/PCM when there is a demand for cooling from the air conditioning system.
ECM/PCM CONNECTORS
a l32P)
ECM/PCM CONNECTOR A {32P)
Wire side of female terminals
ECM/PCM CONNECTORS
A (32P1
Chock tor a short in ihe wi.e(ACS lin6):1. Turn the ignition switch OFF.2. Disconnect the A/C pressure
switch 2P connector.3. Turn the ignition switch ON (ll).
4. Measure vo ltage betweenECM/PCM connector terminals A27 and 820.
Check for a short in the wire (ACS
linel:'1. Turn the ignition switch OFF.2. Disconnect the ECM/PCM connector A (32P).
3. Check lor continuity betweenbody ground and ECM/PCMconnector terminal A27.
Reoair short in lhe wi.e botweonthe ECM/PCM (A271 and rhe A/Cpressure swilch.
Srr66tituto a known{ood ECM/PCt4 tnd rechock. It prascrib€dvoltage is now available, re-plac€ the original ECM/rcM.Soo the air conditioner insoec-tion {see s€ction 22}.
Check to. an opon in tho wi.e(ACC linel:1. Turn the ignition switch OFF.2. Reconnect the A/C pressure
switch 2P conneclor.3. Turn the ignition switch ON (ll).
4. Momentarily connect ECN4/PCM connector terminals A17and 820 with a jumper wire
(To page '! 1-207)
11-206
LGl {BRN/BLK)

\J
Fuol Iniection Air {FlA) Contlol Valve T$ting
1. Start the engine.
2. Remove the vacuum hose from the fitting on the
intake air duct, and connect a vacuum gauge to the
nose.
NOTE: Engine coolant temperature must be below
149"F (65"C).
VACUUM PUMP/GAUGE,
0-30 in.Hg.A973X - 041 -XXXXX
Raise and lower the engine speed, and make sure
the vacuum gauge reading changes as the engine
speed changes.
lf vacuum reading does not change check these
rtems:
. The vacuum lines of FIA system for misrouting,
leakage, breakage and clogging.
. The FIA controt valve for cracks or damage
. The cooling system (see section 10).
Hold the engine at 3,OOO rpm with no load (in Park
or neutral) until the radiator fan comes on, th€n let
it idle and recheck.
lf vacuum reading changes check these items:
a The FIA control valve for cracks or damage.
. The cooling system (see section 10).
11-251