1997 HONDA CIVIC Vacuum

Fuel Supply System
Fuel Injectors
Replacement
@ Do not smoke when working on the tuel systgm, Keep gp6n flames away from your work area
'f. Relieve the fuel pressure (see pages 11-230,231J.
2. Disconnect the connectors from thefuel injectors (D16Y7 engine: Remove the air cleaner).
3. Disconnect the vacuum hoses from thefuel pressure regulator. Placeashoptowel overthefuel return hose, then dis-connect it from the fuel pressure regulator. Disconnect the vacuum hoses and 2P connector from the EVAp purgecontrol solenoid valve.
4. Remove the retainer nuts on the fuel rail.
5. Disconnect the fuel rail.
6. Removethefuel injectors from the intake manifold.
D16Y5, D16Y8 engine:
NOTE: lllustration shows D16Y8 engine.
D16Y5 engine is similar.
12 N.m11.2 kgl.m,8.7 rbt.ft)
12 N.m11.2 lgl.m,8.7 rbt.ftl
.q
wE4
Y
Ve
ffi}Yg
E
O.RINGReplace.
CUSHIONRINGReplace.
O.RINGReplace.
cusl{toNRINGReplace.
SEALRINGReplace.
ffi
E
EV
R
w
t
YEVAPPURGE CONTNOLSOLENOID VALVE
FUEL
11-232

\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

Fuel Supply System
Fuel Pressure Regulator
Te3ting
@ Do not smoke during the tast. Keep open
flamcs away from your work arsa.
1. Attach the special tool(s) to the service port on the
fuel filter (see pages 1 1-230, 231).
Pressure should bo:
except 81642 engine
260 - 310 kPa |'2.7 - 3.2 kgllcrn2,38 - /t6 psil
816A2 engine:
27O - 320 kPa 12.8 - 3.3 kgf/cm,, 40 - 47 psi)
{with the tuel pressure regulator vacuum hose
disconnested and pinched)
Reconnect the vacuum hose to the fuel pressure
regulator.
Check that the fuel pressure rises when the vacuum
hose from the fuel pressure regulator is disconnected
again.
lf the fuel pressure did not rise, replace the fuel
pressure regutalor.
CLAMP
REGULATOR
11-234
Reolacement
@@ Do not smoke while working on luel sys-
tem. Keep open flame away from your work area,
1. Place a shop towel under the fuel pressure regulator,
then relieve fuel pressure (see pages 11-230,231l..
2. Disconnect the vacuum hose and fuel return hose.
3. Remove the two 6 mm retainer bolts and the fuel
pressure regurator.
Apply clean engine oil to a new O-ring. and carefully
install it into its proper position.
Install the fuel pressure regulator in the reverse
order of removal.

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

\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

Emission Control System
Exhaust Gas Recirculation (EGR) System (D16yS engine)
Doscription
The EGR system is designed to reduce oxides of nitrogen emissions (NOx) by recirculating exhaust gas through the EGRvalve and the intake manifold into the combustion chambers. lt is composed of the EGR valve. EGR vacuum conrrot vatve.EGR control solenoid valve. ECM and various sensors.The EcM contains memories for ideal EGR valve lifts for varying operating conditions, The EGR valve lift sensor detectsthe amount of EGR valve lift and sends the information to the ECM. The ECM then compares it with the ideat EGR valve liftwhich is determined by signals sent from the other sensors. lf there is any difference between the two. the EcM cuts cur-rent to the EGR control solenoid valve to reduce vacuum applied to the EGR valve.
EGR CONTROLCVT: SOLENoID vALvE
EGN VALVE LIFT SENSOR
BLK
I
I
11-254

Emission Control System
Exhaust Gas Recirculation (EGR) System (D16Y5 engine with GWI (cont'dl
lTl49il T_he scan tool indicates Diagnostic Trouble Code (OTC) P1491: A malfunction in the Exhaust Gas Recirculation- lEgh) svstem.
CvT lM/T see page 1l-2611:
J
EGR VALVELIFT SENSOR#16 HOSE
PUMP/GAUGE,0- 30 in.HsA973X-041-XXXXX
EGRVALVE
The MIL has been reoorted on.DTC P1491 is stoled.
Problem verification:1. Do the ECM/PCM Reset Proce-du re.2. Connect the SCS service con'
3. Start the engine. Hold theengine at 3,000 rpm with noload {in Park or neutral) untilthe radiator fan comes on,4. Drive the vehicle on the roadfor approx. 10 minutes. Try tokeep the engine speed in the1,700 - 2,500 rpm range.
Intermittonl failure, system is OKat this time. Check for Door con-nections or loose wires at, C144{EGR velve} and ECM/PCM.
ls DTC P l49l indicated?
Check fo. vacuum to ihe EGR
1. Disconnect the No. 16 hose fromthe EGR valve.2. Connect a vacuum pump/gauge to the hose.3. Start the engine and let it idle.
ls there any vacuum?
Check tor a malfunction in theEGR control solenoid valve:'1. Disconnect the EGR controlsolenoid valve 2P connector,2. Becheck the No. 16 hose for
Check vacuum hose routing o,the entire EGR svstem. lf hoserouting is OK, replac€ the EGRcontrol solenoidvalv6.
ls there any vacuum?
Substitute a known-good ECM/PCM and recheck. It symptom/indicalion goes away, replacethe original ECM/PCM.
(To page 11 257)
11-256

\EGR VALVELIFT SENSOR#16 HOSE
I
(From page 11-256)
EGR VALVE LIFT SENSOR3P CONNECTOR lC14.l)
zF vcczI- . ] IYEL/BLU)ll 2l3l---l-r_ 7 |
v-,, ISG2IGRN/BLK) I ^ II{Vts
ECM CONNECTOR D {16P)
PUMP/GAUGE,0 - 30 in.Hs4973X-041-XXXXX
sG2(GRN/BLKIvcc2IYEL/BLU}
Wire side ol temale terminals
PCM CONNECTORS C (31P}'
YES
Wire side of female terminals
1
(cont'd)
1-257
Check fo. a mallunction in theEGF valv€:1. ldove the vacuum pump/gauge
to the EGR valve.2. With the engine at idle, apply
26.7 kPa (200 mmHg,8.0 in.Hg)
ofvacuum to the EGR valve.
Does the engine stall or runrough and does the EGR valvehold vacuum?
Check for an open in the wire
IVCC2linel:1. Turn the ignition switch OFF.2. Disconnect the EGR valve liftsensor 3P connector.3. Turn the ignition switch ON (ll).
4. Measure voltage between theEGR valve lift sensor 3P con'
nector terminals No. 3 and
No.2.
ls lhere approx.5 V?
Check for an oDen in the wire
{VCC2 line}:Measure voltage between theECM/PCM connector terminalsD10 and Dl1 (C18 and C28)*.
Rep.ir open in the wire betweenrhe EGR valve snd ECM/PCM
{Dl0 {C28)*).lsthere approx.5 V?
Sub3titute t known-good ECM/PCM end recheck. lt 3ymptom/indication goos eway, replaceth6 original ECM/PCM.(To page 1l-258)*: '99 - 00 models