For HONDA CIVIC 1997 6.G Workshop Manual

Emission Gontrol System
Exhaust Gas Recirculation System (Dl6Y5 engine with M/Tl (cont'dl
lFrom page 11 263)EGR VALVE6P CONNECTOR {C144}
J
Wire sideof femaletermtnals
J
Check lor an op€n in the wire (E-
EGR line):1. Turn the ignition switch OFF.2. Disconnect the ECM connector,A (32P)trom the ECM.3. Check lor continuity betweenECM connector terminal A7and the EGR valve 6P connec-torterminal No. 6.
Repair open in the wiro botweenthe EGR valv6.nd th€ ECM {A71.
Check tor a short in the wire {E-EGR lin6l:Check for continuity betweenECM connector terminal A7 andbody ground.
Reoair shorl in tho wiro belwe€nthe EGn vake rnd the ECM lA7l.ls there continuity?
Check fo. an open in tho wiro
IGND line):Check for continuity between theEGR valve 6P connector terminalNo.4 and body ground.
R6pai. open in th€ wir. betweenth6 EGF control solenoid v6lveand G101.
Substitute 8 known-good ECMand recheck. It symptom/indica-tion goes away, roplace the origi-nalECM.
CONNECTORA l32P)
2
a
I G101
Q) raur
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Exhaust Gas Recirculation System
The scan tool indicates Diagnostic Trouble
Recirculation (EGRlvalve lift sensor circuit.
(D16Y5 enginel
Code {DTC) P1498: A high voltage problem in the Exhaust Gas
EGR VALVE LlFf SENSOR 3P {M/T: 6Pl CONNECTOR (C1441
cvT:
vcc2{YEL/BLUI
SG2 IGRN/BLK)
IM/T:sG2{GRN/BLKI
Wir€ side ol lemale terminals
ECM CONNECTOR D (16P)
vcc2(YEL/BLUIsG2(GRN/BLK)
Wir€ side of female terminals
PCM CONNECTORS C 131P)'
Wire side oI female terminals
11-265
- The MIL has been reportod on.- DTC P1498 is storod.
Probl€m verification:1. Do the ECM/PCM Reset Proce
dure.2. Stan the engine.
Intermittent tailure, sy3lem is OK
at lhis time. Check tor poor con'
nections or loose wire3 at C144
|EGR valvel and ECM/PCM.
ls DTC P1498 indicated?
Check for an open in tho EGRvalv6 lift sen3or:1. Turn the ignition switch OFF.
2. Disconnect the EGR valve lift
sensor 3P (M/T: 6Pl connector.
3. Turn the ignition switch ON (ll).
4. Measure voltage between the
EGR valve litt sensor 3P lM/T:6P) connector terminals No. 3and No.2.
ls there approx.5 V?
Check lor op€n in th€ wire (SG2
line):Measure voltage between ECM/PCM connector terminals 010 andD1l (C18 and C28)*.
Repair open in tho wiro betwoen
ECM/PCM lDl1 (Cl8)r) and EGR
valvo lift sensor.ls there approx. 5 V?
Substitute . known-good ECM/PCM and recheck. ll symptom/indicrtion goes away, replacothe original ECM/rcM.
*:'99 - 00 D16Y5 engine with CVT

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
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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

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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 Gontrol System
Evaporative Emission (EVAPI Controls (cont'dl
(From page 11-271)
I
ECM/PCM CONNECTOR D I32P}
PGl IBLKI
Check the EVAP purge controlsolenoid valvei1. Reconnect the EVAP purge
control solenoid valve 2P con-nector.2. Connect ECM/PCM connectorterminals A15 and 410 with a
Check for an open or short in thewire (PCS line):Measure voltage between ECM/PCM connector terminal A15 andbody gro!nd.
Does the solenoid valve clickwhen the jumper is connected?
Che'ck for a short in the wir6 {PCSline):1. Turn the ignition switch OFF.2. Disconnect the ECM/PCM con-nector A (32P).
3. Disconnect the EVAP purgecontrol solenoid valve 2P connector.4. Check lor continuity betweenbody ground and ECM/PCMconnector terminal A15.
Repai. short in the wir6s betwoonthe EVAP purge control solanoidvalve and ECM/rcM lA15l.
R€pair op€n in the wir$ betwo€ntho EVAP purge control solenoidvalve and ECM/rcM lA15l.
Check the vacuum lin€3:Check the vacuum lines ol EVAPsystem for misrouting, leakage,breakage and clogging.
Are the vacuum lines OK?
PCS {REO/YEL)
t389t0'tt
12l3'I'tt5t5'11IE1920232a
?5212A2930
PCS {RED/YEL)
23a67E9t0It
12t3'ta't5l617ta1920222321
2a2728A30
0) Pcs {REo/YELI
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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

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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:
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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)

Emission Control System
Evaporative Emission (EVAP) Controls (cont'dl
!
FUEL TANKPRESSURE SENSOR3P CONNECTOR {C7921
PTANK
{LT GRN)
sG2{GRN/BLK)
Wire side of f€mal€ terminals
{From page 11-275)
Check to. ! short in the wiroIPTANK linol:Measure voltage between thefirel tank pressure sensor 3P con-nector No. 3 terminal and No. 2terminal,
ls there approx.5 V?
Check fo. a Short in the wireIPTANK IinoI:1. Turn the ignition switch OFF.2. Disconnect the ECM/PCM con,nector D 116P).3. Check for continuity betweenthe fuel tank pressure sensor3P connector No.3 terminalsand body ground.
Repair thort in thc wire betweantho fuel iank pre$uro 3€naor andECM/FCM tDl5t.
ls there continuity?
Substitute ! known-good ECM/PCM and recheck. lf .ymptom/indication go6s awry, repleco th6origin.l ECM/PCM.
PTANK{LT GRNI
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'99 - 00 models excepi Dl6Y5 engine with M/T:
The scan tool indicates Diagnostic Trouble Code (DTC) P0452: A low voltage problem in the Fuel Tank Pressure
sensor.
The fuel tank pressure sensor converts fuel tank absolute pressure into electrical signals and inputs the ECM/PCM
OUTPUTVOLTAGE(vlt.5
0.5-7 kP.(-g) mmHg,-2 in.Hgl
+7 kP.
150 mmHg,2 in.Hgl
PRESSURE
I
Wire side of lemale terminals
FUEL TANKPRESSURE SENSORSUB.HARNESS6P CONNECTOR (C574 (C568)rl
vcc2(YEL/BLUIsG2{GRN/BLK}
Wire side o{ temale terminals
The MIL has been .eported on.
DTC P0452 is stored
Check the vacuum lines:
Check the vacuum lines of the
fuel tank pressure sensor lor mis-
routing, leakage, breakage and
cloggrng.
Are the vacuum hnes OK?
Problem veritication:1. Do the ECM/PCM Reset Proce-
du re,2. Bemove the fuel fill caP.
3. Turn the ignition switch ON {ll)
4. Monitorthe FTP Sensor voltage
with the Honda PGM Tester' or
measure voltage between body
groLrnd and ECM/PCM connec_
tor terminalA29.
lntermitlent tailure, 3Ystem b OK
at this time. Check for Poor con'
nections or loose wire3 at C131
{located under right side of dash},
C401 {located above under'dash
tuse/relay box), C574 (C568)*
llocdted under access Panel),C792 (tuel rank Prcssure sensorl
and ECM/PCM.
ls there approx.2 5 V?
Check for an open in wire {VCC2
line):1. Turn the ignition switch OFF.
2. Reinstall the ltrel fill caP
3, Remove the access Panel from
the floor.4. Disconnect the fuel tank Pres'sure sensor sub-harness 6P
5. Turn the ignition switch ON (ll).
6. At the access Panel side, mea_
sure voltage between the fuel
tank Pressure sensor sub-nar-
ness 6P connector No 5termi
nal and No. 6 termlnal.
Repair open in tho wire between
th6 fu€l tank Prossuro sen3oa and
the ECM/PCM lc28).ls there approx 5 V?
ECM/PCM CONNECTOR A (32P)
PTANK {LT BLUI
I
ll
(To page '11-278)
(cont'd)

Emission Control System
Evaporative Emission (EVAPI Controls {cont,dlJ
FUEL TANKPRESSURE SENSORSU8-HABNESS6P CONNECTOR 1C574 tC568)rt
PTANK
{LT GRN}
PTANK
ILT GRN}
Wire side of female terminals
(From page 11-277)
Check for a short in the wire{PTANK line):At the access panel side, measure voltage between the fueltank pressure sensor sub-harness6P connector No. 2 terminal andNo. 6 terminal.
ls there approx. 5 V?
Chock lor a Short in the wi.e(PTANK line):1. Turn the ignition switch OFF.2. Disconnect the ECM/PCM con-nector A (32P).
3. Check for continuity betweenthe fuel tank pressure sensorsub-harness 6P connector No.2 terminals and body ground.
Repair short in the wi.e betwsenthe luel tank pressure sensor andECM/PCM {A291.
Subsiitute a known-good ECM/PCM and rechock. lf symptom/indication goes away, replac€ theoriginal ECM/PCM.
11-278