fuel system HONDA CIVIC 1998 6.G Repair Manual

Fuel Supply System
PGM-FI Main Relay (cont'dl
Circuit Troubleshootin g
PGM.FI MAIN RELAY 7P CONNECTOR {C443)
GND{8LK)
Wire side of female terminals
/BLK}
- Engine will not start.- lnsoection of PGM-FI mainrelay and relay harne$.
Check for an open in the wire{GNO line}:l. Turn the ignition switch OFF.2. Disconnect the PGM-Fl mainrelay 7P connector.3. Check for continuity betweenthe PGM Fl main relay 7P con-nector terminal No.3 and bodyground.
Ropai. open in the wir€ betweenthe PGM-FI main .elav and G101.
Check for an open or short in thewire {BAT lin€}:N4easure voltage between thePGM-FI main relay 7P connectorterminal No. 7 and body ground.- Repair open or sho.t in thewire between the PGM-FI mainrelay and the Fl E/M {15 A}fus€.- Replace the Fl E/M (15 Allu3ein the under-hood fuse/relayoox.
ls lhere battery voltage?
Check tor an open or short in thewire {lGl line):1. Turn the ignition switch ON (ll).
2. Measure the voltage betweenthe PGM-Fl main relay 7P con'nector terminal No. 5 and bodyground.- Repair open or short in thewire betwoen the PGM-FI mainrelav and the No. 13 FUELPUMP (15 A)tuse.- R€place the No. 13 FUELPUMP {15 A} tus€ in the under-d.sh fus€/relay box.
ls there battery voltage?
Ch.ck for an open or short in thewire {STS lino}r1. Turn the ignition switch to theSTART (lll) position.NOTE:. M/T: Clutch pedal must beoepresseo.. A/T: Transmission in E or
E position.2, Measure the voltage betweenthe PGM-Fl main relay 7Pconnector terminal No, 2 andbody ground.
12
[,a567
123BAT
{WHTa56,
'96 98 models: (To page 1l 239)'99 - 00 models: (To page I l-240)
11-238,

Fuel Supply System
- Repair op€n or short in thewir€ betlveen the PGM-FI mainrelay and the No. 31 STARTERSIGNAL 17.5 A) fuse.- RoDlace the No. 31 STARTERSIGNAL {7,5 Al tuse in theunder-dash luse/rolay box.
ls there battery voltage?
Check tor an open in the wire(FLR linel:1. Turn the ignition switch OFF.2. Disconnect the ECM/PCM con-nector A (32P).
3. Check for continuity betweenthe PGM-FI main relay 7P con-nector terminal No. 1 and ECM/PCM connector terminal A16.
Repair open in the wir6 botweenthe ECM/PCM (A161 and rhePGM-FI main relay.
Check for an open in the wires{lGPl, lGP2 line3):1. Reconnect the ECM/PCM con-nector A {32P).2. Reconnect the PGM-Fl mainrelay connector.3. Turn the ignition switch ON (ll).
4. Measure voltage betweenECN4/PCM connector terminals81 and 820, and betweenBg and 820.
- Repair open in the wire bet-ween th. ECM/PCM (81, Bg)snd the PGM-F main rolay.- Roplace th€ PGM-FI main relav.
Chock tor an open in th6 ECM/PCM:1. Turn the ignition switch OFF.2. Measure vo ltage betweenECM/PCM connector terminalsA16 and 82 when the ignitionswitch is first turned ON lll) for
Sub3titute . known-good ECM/PCM and rochock. lf prescribedvohege is now available, replacethe original ECM/PCM.
ls there 1.0 V or less?
Chock the PGM-Fl m.in r6lay{see p.ge 11-2371.
PGM-FI Main Relay (cont'd)
_._(9x . qq -gqerll _
PGM.FI MAIN FELAY 7P CONNECTOR {C4€}FLR
ECM/PCM CONNECTORS
A (32P1
Wire side ot female terminals
Wire side of fem6le terminals
ECM/PCM CONNECTOR B {25PIIGP2 {YEL/BLKI
IGRN/YEL}
IGP2(YEL/BLKI
Wire side of female terminals
11-240
IJ
'l'

IFuelTank
'96 - 98 models:
Replacement
I
1. Relieve the fuel pressure (see pages \1-230' 23'll'
2. Remove the seat cushion (see section 20).
3. Remove the access panel from the floor'
4. Disconnect the 2P (C565) and 3P (C564) connectors ('96 D]6Y8 engine (coupe) '97 D16Y/ engine(coupe: KL model'
sedanKL(LX)model).'97D'l6YSengine(coupe:allmodels'sedan:KLmodel'98-allmodels):and6P(C568)connec-
tor),
5. Disconnect the hose and quick-connect fittings (see pag es'l'l-225' 2271
6. Jack up the vehicle, and support it with jackstands'
7. Removethefuel tank cover ('96,'97 model) orthefuel hose joint protector'
8. Bemovethedrain bolt,and drainthefuel into an approved container'
9. Disconnect the hoses {see page r i-izst. Sria" nu"i ihe clamps, then twist hoses as you pull, to avoid damaging them'
10. Place a jack. or other support, under the tank'
11. Remove the strap nuts, and let the straps fall free'
12. Removethefuel tank lf it sticks on the undercoat applied to its mount' caref u lly pry it off the mount'
13.|nsta||thedrainbo|twithanewwasher.thencoatthedrainbo|twithNoxrustl24B,A||owtheNoxrustdryfor20min-
ules.
14. Installthe remaining pans in the reverse order of removal'
SASE GASKETReplace.
BASE GASKETReplace.
!@@ Do not smoke while working on fuel system' Keep open flame away from your work ar'a'
TANKSTRAPS
DRAIN BOLT,19 N.m {5.0 kgt m, 36 lbf.ftl(cont'd)
11-241

Fuel Supply System
Fuel Tank {cont'dl
39 - (xt models:
Replac6ment
o
@ Do not smoke whire working on fuer system. Ke€p open frama away trom your work area.
1. Relievethefuel pressure (see pages 11-230,23'll.
2. Remove the seat cushion lsee section 2O).3, Remove the access panel fromthefloor.
4. Disconnectthe2P (C565) and3P(CS64) connectors and 6p (C569) connecror.5. Disconnect the hose and quick-connect fiftings (see pages 1l-226,22j),6. Jack up the vehicle, and support it with jackstands.
7. Removethefuel hose joint protector and heat shield.8. Removethedrain bolt. and drainthefuel intoan aporoved container.9 Disconnect the hoses (see page 11-226). Slide back the clamps. then twist hoses as you pull, to avoid damagtng rnem.10. Place a jack, or other support, under the tank,11. Remove the strap nuts, and let the straps fallfree,'12. Removethefuel tank. lf itsticks onthe undercoat applied to its mount, carefully pry itoffthe mount.13. Install thedfain boltwith a new washer. then coat the d rain bolt with Noxrust 124B,Allowthe Nox.ust drv for 20 min-utes.
14. Installthe remaining parts in the reverse order of removal,
Replace.
DRAIN BOLT,19 N.m (5.0 kgf.m, 36lbf.ft)
11-242

Intake Air System
Fuel Injection Air (FlA) Controt System I'99 - 00 Dl6yg enginel
Dsscription
When the engine running lengine coolant below 149oF (6S"C)], the fuel Injection Air (FtA) Control Valve sends intake air tothe fuel iniectors.
E> : INTAKEAIR
FUELINJECTOB
11-250

1\
Evaporative Emission (EVAPI Controls
Description
The evaporative emission controls are designed to minimize the amount of fuel vapor escaping to the atmosphere. The
system consists of the foliowing components:
A. Evaporative Emission (EVAP) Control Canisto]
An EVAP control canister is used for the temporary storage of fuel vapor until the fuel vapor can be purged from the
EVAP control canister into the engine and burned.
B. Vapor Purge Control System
EVAP control canister purging is accomplished by drawing fresh air through the EVAP control canister and into a port
on the intake manifold. The purging vacuum is controlled by the EVAP purge control solenoid valve.
I'96 D16Y5 engine,'96 Dl6Y7 engine,'96 D16Y8
engine (sedan),'97 D16Y5 engine,'97 D16Y7
engine (couper KA, KC models, sedan: KA, Kc'
KL iDX) models, hatchback: all models), '97
D 16Y8 engine (sedan: KA, KC models)l
I'96 D16Y8 engine (coupe),'97 D16Y7 engine
(coupe: KL model, sedan: KL (LX) model)"97
D16Y8 engine (coupe: all models, sedan: KL model)'98-all models,'99-all models,'00-all modelsl
I
c.
D.
or
l'lc COMPRESSOR CLUTCH ON
and
INTAKE AIR TEMPERATURE ABOVE 160"F (41'C)
Fuel Tank Vapor Control System
When fuel vapor pressure in the fuel tank is higher than the set value of the EVAP two way valve, the valve opens and
regulates the flow of fuel vapor to the EVAP control canister.
Onboard Refueling Vapor Recovery (ORVRI System {'99 - 00 models}
During refueling. the oRVR {onboard Refueling Vapor Recovery) vent shut valve opens with the pressure in the fuel
tank. and feeds the fuel vapor to the EVAP control canister.
t(cont'd)
11-267
EVAP PURGE CONTROL SOLENOID VALVE DUTY CON-
TROLLED AFTER STARTING ENGINE
ENGINE COOLANT TEMPERATURE ABOVE 154'F {68"C)
INTAKE AIR TEMPERATURE ABOVE 32'F (O'C)
and
VEHICLE SPEED ABOVE O MILE (O KM/h}
ENGINE COOLANT TEMPERATURE ABOVE 154'F (68'C)

Emission Control System
Evaporative Emission IEVAPI Controls (cont'd)
'96 D16Y8 ongins (coupol.'97 D16Y8 €ngino (coups: all mod€ls, sedan: KL model),'98 D16Y5 engine (all mod6lsl,'98
Dl5YB engine {all modols):
{BLK/YEL
From
< No. 15
FUELTANKPRESSURESENSOR
EVAP PURG€CONTROLSOLENOID VALVE
. LT GRN
GRN/BLK
ALTERNATORSP SENSOR(7.5 A)
VARIOUSSENSORS
YEL/BLU
V€NT SHUT
EVAPBYPASSSOLENOIDVALVEL BLU
WHTRED/YEL
L __ LT GRN/
EVAPTWO WAYVALVE
INTAKEMANIFOI.I'
'97 D16Y7 engin. (coupa: KL model, sedan: KL {LX) model},38 Dl6
/ engine:
?:y- -<
FromNo. 15ALTERNATORSP SENSOR17.5 A)
FUELTANKPRESSURESENSOR
YEL/BLULT G]GRN/BLK
LT GRN/WHT
BLU
YEL
EVAPBYPASSRED/
VALVE
EVAPTWO WAVALVE
EVAP CONTROLCANISTER
FUEL FILLCAP
BLK
11-268
FUEL TANK

Emission Control System
Evaporative Emission (EVAPI Controls (cont'd)
'99 - 00 Dl6Yg engine,'99 - 00 Dl6Y5 €ngine,'99 - 00 81642 engine:
FUELTANKPRESSURESENSOR
EVAPBYPASSSOLENOIDVALVE
From
BLK/ - No. 15
YEL _ ALTERNATORSP SENSOR
{7.5 A)
- GRN/BLK
BLU
*=ol
LT GRN/WHT
ONBOARD REFUELING
FUEL TANK
EVAP PURGECONTROLSOLENOID VALVE
EVAPORATIVEEMISSION {EVAP)CONTROLCANISTERFILTER
YEL
LT GRN
VAPOR RECOVERY IONVR) VENTSHUT VALVE
ONBOARD REFUELINGVAPOR RECOVERY IORVN} VAPORRECIRCULATION VALVE
'99 - 00 D16Y7 engine:
EVAP CONTROLCANISTER
BLK/YEL
FromNo. 15< ALTERNATORSP SENSOR{7.5 A}FUELTANKPRESSURESENSOR
EVAPEYPASSSOLENOIDVALVE
- BLULT GNN/WHT
EVAP PURGECONTROLSOLENOIO VALVE
INTAKEMANIFOLD
EVAPTWO WAYVALVE
FUEL TANK
ONBOARD REFUELINGVAPOR RECOVERY {ORVRI VENTSHUT VALVE
EVAPORATIVEEMISSION {EVAPICONTROL
EVAP CONTROL
ONBOARD REFUELINGVAPOR RECOVERY IORVRI VAPORRECIRCULATION VALVE
CANISTERFILTER
YELI
8LK
11-270
CANISTER

Emission Control System
Evaporative Emission (EVAP) Gontrols (cont'd)
'99 - 0O models only:
The scan tool indicates Diagnostic Trouble Code (DTC) P0451: The Fuel Tank Pressure sensor circuit range/oerformance Droblem.
ECM/PCM CONNECTORS
wire side ot femare terminars sG2 IGRN/BLK)
FUEL TANKPRESSURESENSOR
VACUUMPUMP/GAUGE,0 - 30 in.Hg
FUEL TANKPRESSURE SENSORASSEMBLY
EVAP TWOWAY VALVE
IJ
tl'
Ths MIL has been reDortgd on.DTC m/$1 i3 stored.
Check the tuel tank pros3ure ser|-sor:1. Do the ECM/PCM Reset Proce-dure.2. Remove the tuellill cap.3. Turn the ignition switch ON (ll).4. N4onitor the FTP Sensor volt-age with the Honda PGMTester, or measure voltagebetween body ground andECN4/PCM connector terminalsA29 and C18.
ls there approx. 2.5 V7
Check tho tuel tank pressure !on-soa:1. Remove the fuel tank (seepage 11 2421.2. Remove the fuel tank pres-sure sensor assembly fromthe fueltank.3. Connect the fuel tank PressureSensor sub-harness 6P con-nector to the access panelside connector,4. Disconnect the hose betweenthe EVAP two way valvg andthe fuel tank pressure sensor atthe EVAP two way valve end.5. Connect a vacuum pump tothe open end ofthat hose.6. Turn the ignition switch ON (ll).7. Monitor the FTP Sensor volt,age with the Honda PGMTester, or measure voltagebetween ECM/PCM connectorterminals A29 and C18, andcarefully pump vacuum on thehose one stroke at a time.8. The voltage sho!ld smoothlydrop from the stading approx.2.5 V down to approx. '1.5 V.STOP applying vacuum whenthe voltage drops to approx. 1.5V or damage to the fuel tankpressure sensor may occur.
Does the voltage drop toapprox. 1.5 V and hold?
Sub3titute a known-good ECM/PCM and r6check. It symptom/indicltion 90e3 aw.y, replac\. th€original ECM/PCM.
A (32P)
A973X - 041 -
xxxxx
11-274

\J
Fuel Tank Pro3sure sensor 196 D16Y8 engine (coupe).'97 D15Y7 engine {coupe: KL model, sedan: KL (LX) modeu,'97
D16Y8 engine (coupe: all models, sedan: KL model, '98-all models) '99 - 00 D16Y5 engine with M/Tl:
\
PTANK
{LT GRNI
vcc2(YEL/BLU}
Wire side oI female terminals
FUEL TANKPRESSURE SENSOR3P CONNECTOR (C7921
sG2IGRN/8LK)
Foc2l::il":"toolindicatesDiagnosticTroublecode(DTc)P0452:A|owvo|tageprob|emintheFue|TankPressure
The fuel tank pressure sensor converts fuel tank absolute pressure into electrical signals and inputs the EcM/PCM.
OUTPUTVOLTAGEtvt4.5
-? kPa(-50 mmHg,-2 in.Hg)
ECM/PCM CONNECTOR O I16P)
Wire side of female terminals
+7 kPs150 mmHg,2 in.Hg)
PRESSURE
(cont'd)
11-275
- The MIL has been reported on- DTC P0452 is stored.
Check the vacuum lines:
Check the vacuum lines of the
fuel tank pressure sensor for mis-
routing, leakage, breakage and
cloggrng.
Are the vacuum lines OK?
Problem v€ritication:1. Do the ECM/PCM Reset Proce
dure.2. Remove the luel fill caP.
3. Turn the ignition switch ON lll)4. Monitor the FTP Sensor volt_
age with the Honda PGM
Tester, or measure voltage
between bodY ground and
ECM/PCM terminal Dl5.lntermittent tailuro, sYstem i5 OK
dt this timo. Chock for Poot con-
neciion3 or loose wir* at C131
llocatod under right side ot dashl,
C4O1 (located .bove under'da3htuso/ielay box), C574 1C568)*
{located under acc€ss Panell.C792 lfuel tank pressule sen3or)
and EcM/PCM.
ls there approx. 2.5 V?
Check tol an op€n in wite (VCC2
line):1. Turn the ignition switch OFF
2. Reinstallthe fuel fill caP.3. Disconnect the fuel tank Pres'sure sensor 3P connector-4. Turn the ignition switch ON (ll)
5, Measure voltage between the
fuel tank pressure sensor 3P
connector No. l terminal and
No. 2 terminal.
Repair open in the wite betweenthe fuel tank Pr€s3ure a€n3or andth6 EcM/PcM (D1ol.ls there approx. 5 V?
(To page 11'276)