replace HONDA CIVIC 1996 6.G Workshop Manual

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

lntake Air System
Air Cleaner (ACLI
NOTE: Do not clean the ACL element it with com-pressed air {except dry type).
D16Y5, D16Y8, 816A2 engine:
ACL ELEMENTNormal conditions:Replace air cleaner element every30,000 miles (48,000 km) or 24months whichever comes first.S€voae conditions:(Use normal scheduleexcept in dusty conditions)Replace every 15,OOOmiles (24,000 km)or 12 monthswhichever comes first.
D16Y7 engine:
ACL ELEMENTNormal conditions:Replace air cleaner element every30,000 miles (48,000 km) or 24months whichever comes first,Seve.s conditions:(Use normal schedule exceptin dusty conditions)Replace every l5,000
whichever comes first.
11-244
Throttle Cable
Inspection/Adiustment
1. Start the engine. Hold the engine at 3,000 rpm withno load (in Park or neutral) until the radiator fancomes on, then let it idle.
2. Check that the throftle cable operates smoothly withno binding or sticking. Repair as necessary.
3. Check cable free play at the throttle linkage. Cabledeflection shoutd be 10- l2 mm (3/B - 112 in.l.
D16Y5, D16Y8 engine:
CABLEBRACKETLOCKNUT
DEFLECTION10-12mm
BIA- 112 inl
D16Y7 engine:
LOCKNUT
DEFLECTION10- 12 mml3lA - lninl

IThrottle BodY
Description
The throttle bodY is either a single-barrel side-draft type
(D16Y5, D16Y8, 816A2 engine) or a down-draft type
(D16Y/ engine). The lower portion ot the throttle valve is
heated by engine coolant from the cylinder head' The
idle adjusting screw which regulates the bypass air is
located on the top of the throttle body
THROTTLEPOS|T|ON lTPlSENSOR
IDLE AD.'USTINGSCREW
t
In3pection
1. Check that the throttle cable operates smoothly
without binding or sticking.
lf there are any abnormalities, check for:
. Excessive wear or play in the throttle valve shaft'
. StickY or binding throttle lever at the fully closed
Position.. Clearance between throttle stop screw and throt-
tle lever at the fully closed position'
D16Y5, Dl6Y8 engine:
THROTTLE STOP SCREW
{Do not adjust.)
Dl6Y7 ongine:
816A2 engins:
THROTTLE LINK
STOP SCREW
THROTTTE STOP SCREW(Do not adjust.)
Replace the throftle body if thsre is excessive play in the
throttle valve shaft or iJ the shaft is binding or sticking'
(cont'd)
11-247
{Do not adjust.)

Intake Air System
J
Throttle Body (cont'dl
Removal
D16Y5, Dl6Y8, 81642 engine:
D15Y7 engine:
AIR CLEANER
{ACLI
22 N.m12.2 kgl.m,16 rbf.ftl
NOTE:
. Do not adjust the throttle stop screw.. After reassembly, adjust the throttle cable {see page l l-244).. The TP sensor is not removable.
IAT SENSOR
MAP SENSOR
GASKETReplace.
11-248
THROTTLE CABLE

\
lTo420l Th" """n toot indicates Diagnostic Troubte code (DTc) p0420: catatyst sysrem efficiency below threshold.
Description
This system evaluates the catalyst's capacity by means of the Ho2s {Primary and secondary) output during stable driving
conditions. ll deterioration has been detected during two consecutive driving cycles. the MIL comes on and DTC P0420 will
be stored.
NOTE: lf some of the DTCS tisted below are stored at the same time as DTC P0420, troubleshoot those DTCS first. then
recheck for DTC P0420
P0137, P0138: Secondary HO2S (Sensor 2)
Po14'1:Secondary H02S {Sensor 2) Heater
Possibl€ Cause
. TWC Deterioration
. Exhaust system leakage
Troubleshooting Flowchart
I
The MIL has been reported on.
DTC P0420 is stored
Problem verilication:1. Do the ECM/PCM Reset Proce
dure.2. Start the engine Hold the
engine at 3,000 rpm wath no
load {in Park or neutral) until
the radiator fan comes on.
3. Connect the SCS service con
4. Test drive 40 - 55 mph for
approx, two minutes Then
decelerate for at least 3 sec_
onds with the throttle com'pletely closed- Then reduce
the vehicle speed to 35 mph,
and try to hold it until the
readiness code comes on
Intermittent Iailure, system is OK
at this time.ls DTC P0420 indicated?
Check the TWC {see section 9l
lf necessary, replace the TwC

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

\JExhaust Gas Recirculation System (D16Y5 engine with M/T)
M/T:
EGR VALVE 6P CONNECTOB (C14'rl
G10lIBLK}
1
a
PNK
IE.EGRI
Wi16 side of male terminals
I
sG2{GRN/BLK}
vcc2{YEL/BLU)
- Th6 MIL ha3 b€on reponed on.- DTC Pl,{tl is 3tored.
Prcblem verification:1. Do the ECM Reset Procedure.
2. Connect the SCS service con_nector.3. Start the engine. Hold the
engine at 3,000 rpm with no
load (transmission in neutral)
untilthe radiator fan comes on.
4. Drive the vehicle on the road
for approx. 10 minutes. Try to
keep the engine speed in the
1,700 - 2,500 rpm range.
lnlermittont tailure, svalem is OK
at thi3 tim6. Check foi Poor con'
nections or looso wiro3 at Cl/K
IEGR valvsl and ECM.
ls DTC P1491 indicated?
Check tor a malfunction in the
EGR valv6:1. Turn the ignition switch OFF.
2. Disconnect the EGR valve 6P
connector.3. Stanthe engine and let it idle
4. Measure voltage between the
EGR valve 6P connector termi'
nals No.4and No.6.
Check the EGR valve:1. Turn the ignition switch OFF2. Turn the ignition switch ON lll).3. Measure voltage between theEGR valve 6P connector termi
nals No.2 and No.3.
ls there battery voltage?
Substitute a known-good ECM
and recheck. It symptom/indica_tion goes away, replace th€ origi-
nal ECM.
ls there approx.5V?
(To page 11-262)

Emission Control System
Positive Crankcase Ventilation IPCVI System
Descripiion
The Positive Crankcase Ventilation (PCV) system is
designed to prevent blow-by gas from escaping to the
atmosphere. The PCV valve contains a spring-loaded
plunger. When the engine starts, the plunger in the PCV
valve is lifted in proportion to intake manifold vacuum
and the blow-by gas is drawn directly into the intake
manifold.
D15Y5, D16Y8, 816A2 ongins:
BREATHERHOSE
Dl6'|11 6ngin6:
-: aLOW-BY VAPOR-: FnESH AIF
11-266
tJ
lrcpection
1. Check the PCV hoses and connections for leaks and
clogging.
2. At idle, make sure there is a clicking sound from the
PCV valve when the hose between the PCV valve
and the intake manifold is lightly pinched with your
fingers or pliers,
D16Y5, D16Y8 ongins:
BREATHERHOSE
PCV VALVE
Gently pinch here.
Bl6A2 engins:VALVE
lf there is no clicking sound, check the PCV valve
grommet for cracks and damage. If the grommet is
OK, replace the PCV valve and recheck.
PCV

J\
(From page 11-272)D16Y5 engine:
JUMPER WIRE
D16Y7, D16Y8 engine
VACUUMPUMP/GAUGE,
VACUUMPUMP/GAUGE,0 - 30 in.HgAs73x - 0il1 -
xxxxx
0 - 30 in.HgA973X -
otl -
xxxxx
I
EVAP CONTROLCANISTER
ECM/PCM CONNECTOH D I32PI
VACUUM/PBESSUREGAUGE0-4in.Hg07JAZ - 0010008
Wire side otfemale terminals
D16Y7, Dl6Y8 engine:
t
VACUUM/PRESSUREGAUGE0-4 in.Hgo?JAZ - 001fl)OB(cont'd)
11-273
PGl IBLKI
Check lhe EVAP Purge control
solsnoid valve:
1. Disconnect the vacuum hose
from the EVAP controlcanister'
2. Connect the vacuum PumP to
the hose and aPPIY vacuum
Does it hold vacuum?
Check the EVAP control canister:
1. Reconnect the vacuum hose to
the EVAP control canlster.
2. Connect the vacuum/Pressuregaugeto the Purge aar hose
3. Connect ECM/PCM connector
terminals A15 and A10 with a
iumper wire.4. Start the engine5. Check the vacuum
Check the EVAP two way valve(see page 11-193)
Does the EVAP two waY valveReplace the EVAP two wsY valve.
Sub3titute a known-good ECM/
PCM .nd recheck. lt symPtom/
indicrtion go6s away, rePlace the
original ECM/PCM.
D16Y5 sngin€: