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
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)
\
'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)
\
Fue| Tank Pr€ssure sensor 196 Dr6Y8 engine (coupe},,97 D16Y7 angino (coupo: KL mode|' 3edan: KL (Lxl modg||',97
Dl6Y8 engine (coupe: all modeb, sedan: Ki model.'98'all modols) 39 - 0O Dl6Y5 ongins with M/Tl:
rFoG'l::;Jl"too|indicatesDiagnosticTroub|ecode(oTc)P0453;Ahighvo|tageprob|emintheFue|TankPressure
ECM/PCM CONNECTOR D Il6PI
PTANKILT GRNI
\
Wire side of tgmale torminals
FUEL TANKPRESSURE SENSOR3P CONNECTOR (C792)
vcc2(YEL/BLU}
sG2(GRN/BLKI
Wire sid€ of female terminals
I
sG2IGRN/BLKI
PTANKIGBN/RED}
(cont'd)
11-279
The MIL has beon reponed on
DTC P0453 b stored.
Check the vacuum lines:
Check the vacuum lines oI the
fueltank pressure sensor for mis-
routing, leakage, breakage and
clogging.
Are the vacuum lines OK?
Problem verification:1. Do the ECM/PCM Reset Proce-
dure.2. Femove the fuel fill cap
3. Turn the ignition switch oN (ll).
4. Monitor the FTP Sensor volt-
age with the Honda PGM
Tester, or measure voltage
between bodY ground and
ECM/PCM connector termrnal
D15.
lntormittont t iluro, 3Ystem is OK
at this time. Check lot Poor con_
noctiona or loo3e wirat at C131
{loc.ted undor right 3id6 of d8hl,
CaOl llocatod rbov. under-dalh
fus6/relay boxl, C574 (C568lr
llocatod und6l accoss Pan6ll,C792 lfuel tank Preasulo aonlorl
end ECM/PCM.
ls there approx. 2 5 V?
Check for an oPen in the wire(SG2line):1. Turn the ignition switch OFF.
2. Reinstall the fuellill 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 terminals No. 1 and
No.2.
Ropair opon in the wira b€tw€sn
the fuel tank prasure sonlor and
ECM/PCM (Dl1).ls there aPProx. 5 V?
Check for an open in the wire(PTANK line):Measure voltage between the
fueltank Pressure sensor 3P con-
nector No. 3 terminal and No. 2
termrnal,
ls there approx. 5 V?
*: coupe
{To page 11-280)
\
'99 - 0O modols except Dl5Y5 engine with M/T:
rFo45'::n":"tooIindicatesDiagnosticTroub|ecode(DTc)P0453:Ahighvo|tageprob|emintheFUelTankPressure
Wire side of temale terminals
FUEL TANKPRESSUNE SENSOR
SUB.HARNESS6P CONNECTOR {C574 (C568)}}
vcc2{YEL/BLUI
sG2IGRN/BLK)
Wire side of female terminals
PTANK{LT GRNI
(cont'd)
11-281
ECM/PCM CONNECTOR A {32P)
PTANK {LT GRN)
The MIL has been reported on.
DTC P0453 is stored.
Check the vacuum lines:
Check the vacuum lines ot the
fuel tank pressure sensor for mis-
routing, leakage, breakage and
clogging.
Are the vacuum lines OK?
Problem verilication:1. Do the ECM/PCM Reset Proce-
du re,2. Remove the fuel fill caP
3. Turn the ignition switch ON (ll).
4. Monitor the FTP Sensor volt'
age with the Honda PGM
Tester, or measure voltage
between body ground and
ECM/PCM connector terminalA.29.
lntermittent failuro. svstem b OK
at this time. Check for Poor con_
noctions or loo3€ wire3 at C131
{located under tight side of dash),
C4Ol {located above underdash
fuse/relay boxl, C57{ (C5681'
llocaled unde. access Panell,C792 {fuel tank Pressure sensorl
aod ECM/PCM.
ls there approx.2.5 V?
Ch€ck for an open in the wira
{SG2line):1. Turn the ignition switch OFF.
2. Reinstall the fuel fill caP
3. Remove the access Panellrom the floor.
4. Disconnect the fuel tank Pres-sure sensor sub-harness 6P
5. Turn the ignition switch ON (ll)
6, At the access Panelside, mea-
sure voltage between the fuel
tank pressure sensor sub_har-
ness 6P connector termlnals
No.5 and No.6.
Repair open in the wire between
the fueliank Pres3ure 3ensor and
ECM/PCM {Cl8).ls there approx.5 V?
Check lor an oPen in the wire
{PTANK linel:At the access Panel side, mea
sure voltage between the fuel
tank pressure sensor suo_harness
6P connector No. 2 terminal and
No. 6 terminal.
ls there approx. 5 V?
(To page 11.282)
Troubleshootin g Procedures
Chccking the Diagnostic Trouble Code IDTC)with an OBD ll Scan tool or Honda PGM Tester
when the PCM senses an abnormality in the input or output systems, the pl indicator light in the gauge assembly willblink. When the 16P Data Link Connector (DLC) (located under the dash on the driver,s side) is connected to the OBD llScan Tool or Honda PGM Tester as shown, the scan tool or tester will indicate the Diagnostic Trouble Code (DTC) whenthe ignition switch is turned ON{ll).
lf the El indicator light or the MIL has been reported on, or lf a driveability problem is suspected, follow this procedure:
1. Connect the OBD ll Scan Tool (conforming to SAE J19781 or Honda PGM Tester to rhe 16p DLC. (See the OBD ll ScanTool or Honda PGM Tester user's manual for specific instructions. lf you are using the Honda PGM Tester, make sure itis set to the SAE DTC type.)
2. Turn the ignition switch ON (lll, and observe the DTC on the screen,3, Record all fuel and emission DTCS, A/T DTCS, and freeze data.4 lf there is a fuel and emissions DTC, first checkthe fuel and emissions system as indicated bythe DTC (except for DTCP0700). DTC P0700 means there is one or more A,/T DTC, and no problems were detected in the fuel and emissions cir-cuit of the PCM.
5. Write down the radio station oresets.
6. Reset the memory with the PGM Tester or by removing the BACK UP fuse in the passenger's under-dash fuse/relay boxfor more than 10 seconds.
7. Drive the vehicle for several minutes at speeds over 30 mph (50 km/hr), and then recheck for DTCS. lf the A"/T DTCreturns, go to the Symptom-to Component Chart on pages 14-52 and 14-53 for'96 - 98 models, and pages 14-54 and14-55 for the'99 - 00 models, lf the DTC does not return, there was an intermittent problem within the circuit. Makesure all pins and terminals in the circuit are tight, and then go to step g.
8. Reset the radio preset stations, and set the clock.
OBD ll SCAN TOOL orHONDA PGM TESTER
DAYA LINK CONNECTOR {16P}
14-44