1998 HONDA CIVIC Fuel pump

Fuel Supply System
System Description
The fuel supply system consists of a fuel tank, in-tank
high pressure fuel pump, PGM-FI main relay, fuelfilter,
fuel pressure regulator, fuel injectors. and fuel delivery
and return lines. This system delivers pressure-regu-
lated fuel to the fuel injectors and cuts the fuel delivery
when the engine is not running.
Fuel Pressure l'96 Modelsl
Relieving
Before disconnecting fuel pipes or hoses, release pres-
sure from the system by loosening the 6 mm service
bolt on top of the fuel filter.
. Do not smoke whil6 working on the fuel system.
Kgsp opon flames or sparks away from youl work
area.
. Be sure to relieve fuel pressure while the ignition
switch is off.
1. Write down the frequencies for the radio's preset
buttons.
2. Disconnect the battery negative cable from the bat-
tery negative terminal.
3. Remove the fuelfill cap,
4. Use a box end wrench on the 6 mm service bolt at
the fuel filter while holding the special banjo bolt
with another wrench,
5. Place a rag or shop towel over the 6 mm service bolt.
6, Slowly loosen the 6 mm service bolt one complete
rurn.
. A fuel pressure gauge can be attached at the 6 mm
service bolt hole.
. Always reDlace the washer between the service
bolt and the special banjo bolt whenever the ser-
vice bolt is loosened.
. Replace all washers whenever the bolts are
removeo.
11-230
Inspoction
1. Relieve fuel pressure.
2. Remove the service bolt on the fuel filter while hold-
ing the banjo bolt with another wrench. Attach the
special tool.
FUELPRESSUREGAUGE07406 - 00ir0(x)1
Start the engine. Measure the fuel pressure with the
engine idling and the vacuum hose of the fuel pres-
sure regulator disconnected from the fuel pressure
regulator and pinched. lf the engine will not start,
turn the ignition switch ON (ll), wait for two sec-
onds, turn it off, then back on again and read the
fuel pressure.
Pr€3sure should bo:
260 - 310 kPa (2.7 - 3.2 kgt/cmr, 38 - 46 psi)
Reconnect vacuum hose to the fuel pressure regulator,
Pressure should bo:
200 - 25O kPa l2.O - 2.5 kgf/cm', 28 - 36 psil
lf the fuel pressure is not as specified, first check the
fuel pump {see page 11-2361. lf the fuel pump is OK,
check the following:
. lf the fuel pressure is higher than specified,
inspect for;- Pinched or clogged fuel return hose or line.- Faulty fuel pressure regulator (see page 11-234).. lf the fuel pressure is lower than specified, inspect
for:- Clogged fuelfilter.- Faulty fuel pressure regulator {see page 11-234).- Fuel line leakage.
REGULATOB

tJFuel Pressure {'97 and later Models)
ReliGving
Before disconnecting tuel pipes or hoses, release pres-
sure from the system by loosening the 12 mm banjo
bolt on top of the fuel filter.
@o Do not smoke whilo working on the fuel sy3lom.
Ksgp op€n flames or sparks away tlom Your work
arga.
. Be sure to relieve fuel pressule while the ignition
swhch is off.
1. Write down the frequencies for the radio's preset
buttons,
2. Disconnect the battery negative cable from the bat-
tery negative terminal.
3. Remove the fuel fill cap.
Use a box end wrench on the 12 mm banjo bolt at
the fuel filter while holding the fuel filter with anoth-
er wrench.
Place a rag or shop towel over the 12 mm banio bolt.
Slowly loosen the 12 mm banjo bolt one complete
turn.
4.
I
12 mm BAtt OBOLT33 N.m (3.i1 kgf m,25 tbf.f0
NOTE: Replace all the washers whenever the 12
mm banio bolt is loosened or removed.
Inspaqtion
1. Relieve fuel pressure.
2. Remove the 12 mm banjo bolt from the fuel filter
while holding the fuel Jilter with another wrench
Attach the special tools.
3. Start the enginethe fuel Pressure with the
engine idling and the vacuum hose of the fuel pres-
sure regulator disconnected from the fuel pressure
regulator and pinched lfthe engine will not start, turn
the ignition switch ON {ll), wait for two seconds, turn
it off, then back on again and read the fuel pressure'
Pr$3uro ehould be:
excepi 816A2 sngine:
260 - 310 kPa {2'7 - 3.2 kgf/cm" 38 - {6 Fi}
B16A2 engine:
27O -32O kPa P.8 - 3'3 kgf/cm', '10 - 47 psi)
4. Reconnect vacuum hoso to the fuel pressure regulator'
Pre33ure 3hould be:
except B16A2 engin€:
2OO - 250 kPa {2.0 - 2'5 kgf/cm', 28 - 36 psi)
B16A2 engino:
210 - 260 kPa 121 - 2.6 ksf/cm', 30 - 37 psi)
lf the fuel pressure is not as specified, first check the
fuel pump (see page 11-236) lfthetuel pumpisoK,
check tho following:
. lf the fuel pressure is higher than specified,
inspect for:- Pinched or clogged fuel return hose or line.
- Faulty fuel pressure regulator (see page 11-
2341.
. lf the fuel pressure is lower than specified, inspect
for:- Clogged fuel filter.
- Faulty fuel pressure regulator (see page l1-
2341.- Fuel line leakage.
FUEL PRESSUREADAPTER BOLT, 12 mm
tguxt8-PD6-0101
CLAMP
REGULATOR
11-231

\J
81642 engine:
EVAP
12 N.m
{1.2 kgl m;8.? lbt.ft)
FUELPRESSUREREGULATOR
O.RINGReplace.
cusHloNRINGReplace.
PURGE CONTROLSOLENOID VALVE
\
SEALRINGReplace.
7. Slide new cushion rings onto the fuel injectors.
8. Coat newO-ringswith clean engineoil, and putthem onthefuel injectors.
9. Insert the fuel injectors into the fuel rail first.
10. Coatnewseal rings with clean engine oil,and press them intothe intake manifold.
11. To prevent damage to the O-rings, installthe fuel injectors inthefuel rail first, then install them inthe intake manifold.
'12. Install and tighten the retainer nuts.
13. Connect the vacuum hoses and fuel return hose to the fuel pressure regulator, Connect the vacuum hoses and 2P
connector to the EVAP purge control solenoid valve.
14. Install the connectors on the fuel inl'ectors (D16YI engine; Install the air cleaner).
15. Turn the ignition switch ON (ll), butdo not operate the starter. After the tuel pump runs for approximately two seconds,
the fuel pressure in the fuel line rises. Repeat this two or three times, then check whether there is any fuel leakage.
11-233

I
FuelFilter
Replacement
r@. Do not smoke whilc working on fuel system. Keep
open flame away from your work arsa.
. While replacing the tuel filter, be catelul to koep a
sale distance betwoen battery torminals and any
tools.
The fuel filter should be replaced whenever the fuel
pressure drops below the specified value [260 - 310 kPa
12.7 - 3.2 ksl/cm',38 - 46 psi), |270 - 320 kPa (2.8 - 3 3
kgf/cm,, 40 - 47 psi))* with the fuel pressure regulator
vacuum hose disconnected and pinchedl after making
sure that the fuel pump and the fuel pressure regulator
are OK. *: 81642 engine
1. Place a shop towel under and around the fuelfilter.
2. Relieve fuel pressure (see pages 11-230,231]-
Remove the 12 mm banjo bolt and the fuel feed
pipe from the fuel filter, while supporting it with the
another wrench, as shown.
Remove the fuel filter ciamp and fuel filter'
lnstall the new fuel filter in the reverse order
removal, and note these items:
a When assembling, use new washers as shown
. Clean the flared joint of high pressure hoses
thoroughly before reconnecting them.
I
,96 MODELS:
(3.4 kgl.m,25 rbf.ftl
,97 AND LATER MODELS:
12 mmBANJOBOLT33 N.m
12 mmBANJOBOLT33 N.mt3.4 kgf m,25 lbf.fr)
\i(o-r
)
11-235

Fuel Supply System
Fuel Pump
Testing
!@ Do not smoke during the test, Keep open
flame away from your work atea,
lf you suspect a problem with the fuel pump, check that the
fuel pump actually runs; when it is ON (ll), you will hear
some noise if you hold your ear to the fuel fill port with the
fuel fill cap removed. The fuel pump should run for two
seconds when ignition switch is first turned ON (ll). lf the
fuel pump does not make noise, check it as follows:
L Remove the seat cushion {see section 20).
2. Remove the access panel from the floor.
3. Make sure the ignition switch is OFF, then discon-
nect the Iueltank 2P connector.
4. Connect the PGM-FI main relay 7P connector termi-
nal No. 4 and No. 5 with a jumper wire.
PGM-R MAIN RELAY 7P CONNECTOR lC4,(|l
FUEL PUMP
IYEL/GRN}
IGN 1(YEL/GRNI
tcs6s)
FUEL PUMP(YEL/GRNI
Wire side oftemale torminals
JUMPER WIRE
Wire side of temale terminals
Check that battery voltage is available between the
fuel pump connector terminal No. 1 and body ground
when the ignition switch is turned ON (ll).
CONNECTOR
=
[t
L3l .i)
T
lf battery voltage is available, check the fuel pump
ground. lf the ground is OK, replace the fuel pump.
lf there is no voltage, check the wire harness (see
page 11-238).
11-236
Replacement
@E Do not smoke while working on tuel svs-
tem. Keep open llames away from your work area.
1. Remove the seat cushion (see section 20).
2. Remove the access panel trom the floor.
3. Disconnect the 2P connector from the fuel pump.
4. Remove the fuel pump mounting nuts.
5. Remove the fuel pump from the fuel tank.
6. Install pans in the reverse order of removal.
ACCESS PANEL
i

I
PGM-FlMain Relay
Description
The PGM-Fl main relav actuallv contains two individual
relays. This relay is located at the right side of the cowl.
One relay is energized whenever the ignition is on which
supplies the battery voltage to the ECM/PCM, power to
the luel iniectors, and power for the second relay. The
second relay is energized lor two seconds when the igni-
tion is switched ON (lll, and when the engine is running,
to supply power to the luel pump.
PGM-FIMAIN RELAY
J
I
t
FUEL PUMP
Relay Testing
NOTE:
. It the engine starts and continues lo run. the PGM Fl
main relay is OK.
. Use the terminal numbers below;
ignore the terminal numbers molded into the relay,
1. Remove the PGM Fl main relay.
2. Attach the battery positive terminal to the No. 2 ter-
minal and the battery negative terminal to the No 1
terminal of the PGM-Fl main relay. Then check for
continuity between the No.5 terminal and No 4ter-
minal of the PGM Fl main relay.
. lf there is continuity, go on to step 3.
. lf there is nocontinuity, replacethe PGM-Fl main
relay and retest.No. 3No. 1
To lGN. 1
To GROUND
To ST. SWITCH
To ECM/PCM {A161
To 8AT O
To ECM/PCM{(a11, A241, (81. B9l*l
To FUEL PUMP.r '99 model
3.Altach the batterv positive terminal to the No.5 ter-
minal and the battery negative terminal to the No. 3
terminal of the PGM-Fl main relay. Then check that
there is continuity between the No. 7 terminal and
No. 6 terminal of the PGM-Fl main relay.
. lf there is continuity, go on to step 4
. lf there is nocontinuity, replacethePGM-Fl main
relay and retest.
Attach the battery positive terminal to the No. 6 ter-
minal and the battery negative terminal to the No. 1
terminal of the PGM Fl main relay. Then check that
there is continuity between the No. 5 terminal and
No. 4 terminal of the PGM-Fi main relay.
. lf there is continuity, the PGM-Fl main relay is OK.
lf the fuel pump still does not work, go to Harness
Testing on the next page.
. lf there is no continuity, replace the PGM Fl main
4.
(cont'd)
11-237
relay and retest.

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,

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