Page 185 of 1413
Cooling
lllustrated Index
Radiator
Replacement ............................... 1 O-4
Engine Goolant Refilling and
Bleeding10-5
Cap Testing ............... 10-6
Pressure Testing ......... 10-6
Thermostat
Rep|acement ............................... 1 O-7
Testing .....1O'7
Water Pump
lllustrated Index ......... . 10-8
Inspection .10-9
Replacement ............................... 1 O-9
10-2
Page 186 of 1413

lllustrated Index
@ sy"t". is under high plessure when engine
is hot. To avoid dsnger of relsssing scalding engine
coolant. remove cap only when engine is cool.
Total Cooling System Capacity (lncluding heater and
r€servoirl
Bl8Bl engine:
Mfl: 6.4 | {6.8 US qt, 5.6 lmp qt}
AlTt 6.7 | {7.1 US qt, 5.9 lmp qt}
Bl8Cl engine:
Mfi: 6.7 t {7.1 US qt, 5.9 lmp qt}
CAUTION: lf any engine coolant spills on paint€d por-
tions ot the body, rinse it ofl immediately.
NOTE:
a Check all cooling system hoses for damage. leaks or
deterioration and replace if necessary.
a Check all hose clamps and retighten if necessary.
a Use new O-rings when reassembling.
CONDENSERFAN SHROUD{soe soction 221
6 x 1.O mm7 N.m (O.7 kgt.m. 5 lbf.ftl
ATF COOLERHOSES{81881 6ngine)
RADIATOREngine coolant refilling and bleeding,page 10-5Leak test, page 'l0-6
Inspect soldered joints andseams for leaks.Elow out dirt from betweencore fins with compressed air.lf insects, etc., are clogging.adiator, wash them off withlow pressure water,
S!
P
R
U
COOLANTRESERVOIR
5x0.8mm4.4 N.m (O.45 kgf.m,3.3 lbl.fr)
M/T: Manual t.anamiaaionA/T: Automatic t.ansmiasionATF: Automatic t.ansmission fluid
\*
*)
FAN SHROUD
10-2
Page 188 of 1413
Radiator
Replacement
1.Drain the engine coolant.
Remove the upper and lower radiator hoses, and ATF
cooter noses.
Disconnect the fan motor connectors.
Remove the radiator upper brackets, then pull up the
radiator.
5. Remove the fan shroud assemblies and other parts
from radiato..
lnstall the radiator in the reverse order of removal:
NOTE:
a Set the upper and lower cushions securely.
a Fill the radiator and bleed the air.4.
UPPER BRACKETAND CUSHTOl{
RADIATOR CAP
t
e
6 x l.O mm9.8 N.m (1.O kgt.m,7.2 rbf.ft)
6 x 1.0 mm9.8 il.m 11.O kgt'm,7.2 lbr.ftl
FAN MOTOR
CUSHION
SHROUDO-RINGReplace.
6 x 1.0 mm9.8 N.m ('l.O kgl.m,7.2 tbl.ttl
DRAIN PLUG
LOWER RADIATORHOSE
Page 189 of 1413

@ ne-oving the radiator cap while the engine
is hot can cause the engine coolant to splay out, seri-
ously scalding you. Always let the engine and radiatol
cool down betore removing the radiator cap.
CAUTION: When poudng engine coolant, be sure to shut
the relay box lid and not to let coolant spill on the elec-
tlical pans or the paint. ll any coolant spills, rinse it otf
immediately.
1. Slide the heater temperature control lever to maxi-
mum heat.
Make sure the engine and radiator are cool to the
touch.
2. Remove the radiator cao.
3. Loosen the drain plug on the bottom of the radiator,
and remove the drain bolt from the enoine block. Let
the coolant drain out.
ENGINE DRAIN BOLT78 N.m {8,O kgt.m, 58 lbt.ftlApply liquid gasker tobolt thread when installing.WASHERReplace.
5.
Remove the reservoir from its holder by pulling it
straight up. Drain the coolant, then put the reservoir
back in its holder.
When the coolant stops draining, apply liquid gasket
to the drain bolt threads, then reinstallthe bolt with
a new washer. Tighten it securely
6. Tighten the radiator drain plug securely.
7. Mix the recommended antifreeze/coolant with an
equal amount of water in a clean container.
NOTE:
. Use only HONDA-RECOMMENOED antifreeze/
coolant.
a For best corrosion protection, the engine coolant
concentrations must be maintained year-round at
50% MINIMUM. Coolant concentrations less than
50% may not provide sufficient protection
against corrosion or freezing.
CAUTION:
a Do not mix ditterent blands ot anti-freeze/
coolants.
a Do not use additional rust inhibitois or anti-rust
products; they may not bs compatibl€ with the
recommgndsd engins coolant.
Engin€ Coolant Retill Capacity: including reservoir
{0.6 t (0.6 US qt, 0.5 lmp qt)).
81881 engine:
MlTt 4.4 | (4.6 US qt, 3.9 lmp qr)
Afft 4.7 [ (5.O US qt,4.1 lmp qt]
Bl8Cl engine:
Mnt 4.7 | (5.0 US qt.4.1 lmp qt)
8. Pour coolant into the radiator up to the base of the
filler neck.
9. Loosen the bleed bolt on top of the engine. Tighten
it again when coolant comes out in a steady stream
with no bubbles.
BLEED BOLT
1O. Refill the radiator to the base of the tiller neck. Put
the cap on the radiator. and tighten it only to the tirst
stop, Stan the engine and let it run until it warms
up (the radiator cooling fan comes on at leasttwice).
11. Turn oft the engine. Check the level in the radiator,
and add coolant it needed. Install the radiator caD,
and tighten it fully.
'1 2. Fill thereservoirto the MAX mark. lnstallthe reser-
voir cap.
9.8 N.m (1.O kgl.m, 7.2 lbf.ftl
Engine Coolant Refilling and Bleeding
10-5
Page 190 of 1413
Radiator
Cap Testing
1.Remove the radiator cap, wet its seal with engine
coolant, then install it on the pressure tester.
Apply a pressure ol:
93- 123 kPa(O.95- 1.25 kgJ/cm', 13.5- 1 7.8 psi)
Check for a drop in pressure.
2.
3.
PRESSURE TESTER
Pressure Testing
1.Wait until the 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 to the radiator and apply
a pressure of:
93- 1 23 kPa(O.95- 1.25 kgf/cm,. 13.5-17.8 psi)
Inspect for engine coolant leaks and a dfop in
pressure,
Remove the tester and reinstall the radiator cap.
NOTE:
a Check for engine oil in the engine coolant and/or
coolant in the engine oil.
a Check for ATF in the engine coolant and/or
coolant in the ATF (A/T).
10-6
Page 209 of 1413
lBl lcl
IT
tl
] I neonr-x
RED/WXT
c449 - C553F- GR[{/OR]{
To RADIATOR FAt{RELAY, COI{D€I{SERFAI{ RELAY
To A/C COTT|PfiESSORCLUTCH RELAY
To A/C SWITCH
(cont'd)
11-17
GAUGE ASSEMALY
{!L rNDrcAToR
["'
Page 232 of 1413

PGM-FI System
System Description
ENGINE CONTROL MODULE (ECMIOUTPUTS
PGM-Fl System
The PGM-Fl system on this model is a sequential multipon fuel injection system,
Fuol Iniector Timing and Duration
The ECM contains memories tor the basic discharge durations at various engine speeds and manifold pressures. Thebasic discharge duration, after being read out from the memory, is turther modilied by signals sent from vanous sensofsto obtain the final discharge duration.
ldle Air Control
ldle Air Control Valve (lAC Vatve)
When the engine is cold, the A/C compressor is on, the transmission is in gear (A/T only) the brake pedal is depressed,the P/S load is high, or the alternalor is charging, the ECM controls current to the IAC Valve to maintain correct idle soeed.
lgnition Timing Controla The ECM contains mamories for basic ignition timing at various engine speeds and manifold pressures. lgnition timingis also adjusted for engine coolant temperature.a A Knock Control System is also used. when detonation is detected by the knock sensof. the ignition timing is retarded(B18Cl engine).
Other Control Functions
1. Starting Control
When the engine is started. the ECM provides a rich mixture by increasing fuel injector duration.2. Fuel Pump Control
a When the ignition switch is initially turned on, the ECM supplies ground to the PGM-Fl main relay that suppliescurrent to the fuel pump tor two seconds to pressurize the tuel system.a When the engine is running, the ECM supplies gfound to the PGM-Fl main relay that supplies current to the fuel pump.a When the engine is not running and the ignition is on, the ECM cuts ground to the PGM-FI main relav which cutscurrent to the fuel pump.
TDC/CKP/CYP Sensor
MAP Senso.
ECT Sensor
IAT Sensor
TP Sensor
HO2S
vss
BARO Sensor
ELD
Starter Signal
ALT FR Signal
Air Conditioning Signal
A/T Gear Position Signal
Battery Voltage {lcN. 1)
Brake Switch Signal
PSP Switch Signal
Knock Sensor'
VTEC Pressure Switchr
Fuel-lnjectors
PGM-FI Main Relay (Fuel Pump)
MIL
IAC Valve
A/C Compressor Clutch Relay
Radiator Fan Relav
Condenser Fan Relav
ALT
rcM
EVAP Purge Control Solenoid
HO2S Heater
VTEC Solenoid Valve'
IAB Control Solenoid Valve*
lFuet tnjector Timing and Duration]
I Electr..l"ldle Contr;il
Fit'e' contr; Funcrfit
l6tio; Ttntrlg c..trol
tEcM aack-,rp Functiorlsl
': 818C 1 €ngine
11-40
Page 238 of 1413

PGM-FI System
Heated Oxygen Sensor lHO2Sl
ztRcot{lAELEiIE'{T
HEATER
- --.'!- - -__-
lrPl _l !l-
-fi-l: The Malfunction Indicator Lamp (MlL) indicates Diagnostic Troubls Code (DTC) 1: A problsm in
/? the Heated Oxygen Sonsor (HO2S| circuit.
The Heated Oxygen Sensor IHO2S) det€cts th6 oxygon contont in th6 exhaust gas and signals th6 ECM. In operation,
the ECM receiv€s th6 signals trom the sensor and vari€s the duration during which tu6l is iniocted. To stabilize thd sen-aor's output, tho sensor has 8n intarnal heater and the sensor olemant is coatod with a catslyst. The HO2S is installod
in TWC housing (B18Cl engine) or exhaust pipe B (Bl8Bl €ngine).
sEl{SORTERMII{ALS
:tz-t6l-/ --.- \
VOLTAGE (V}sTotcHtoltETncAIR-FUEL BANO
HEATEBTEBMIT{ALSRICH - AN. - LEAI{FUELRATIO- Th! mll h.. bo.n raportad on.- Wlth thr SCS rhon coon cto.connoctad lr.. p!9. 1t-341,cod. t l. Indlcltrd.
Oo th€ ECM Res€t Procodure {soopag€ 11-35).
Stan the 6ngine. Hold th6 engine
A3,qgq rpm with no load {A/T in
Lryl or lll position, M/T in nourralluntil the radiator lan com6s on.then lot it idle lor ot least on6minutg beforo road t€6tin0.
Connoct ths SCS short connoctorto th6 sorvic€ check connectorlsoo p.g6 1 1-34).
Rood t€st witlthe automatictransmission in L?l position (M/T:4th gear).Stsrting st l,600 rpm, acc6lorateu6ing wide open throttlo for atlesgt 5 seconds. Thsn dgcol€rstefor at lorst 5 s€conds with th€throttlo completoly closed.
Intarmittd[ t llurc, lyri.m b Of!l thla tlmc. Ch.ck lor poor con-nacdona o? loota wlrat |l C223(loc.trd at right $ock towo.l,Cr 13 (HO2S| lnd ECM.
Ooes the MIL blink and doos itindic6t6 cod6 1?
Go to plga and partonn tad fotcod. 43 lr.a p.go l1-501.
1 1-46