1997 HONDA CR-V Fuel pressure valve

Ch€ck tor rn opon in tha wiioa(lGP lino.):1. Disconnectthe fuel inj€ctor andIAC valve connectors.2. Turn the ignition switch ON {ll}.3. Measure voltage betweenbody ground and ECM/PCMconn€ctor terminals B'l and89 individually.
- Repaii opon in th6 wirc{3lbetw.6n tho ECM/PCM (B1.
Bgl lnd tho PGM-FI mainroby.- Chock for poor connactionsor loo3€ wiJo3 at the PGM-FImain ralry.- T.st the PGM-FI mtin r.lay(soo p.ge 11-1871.
ls there battery voltage?
Chack for an opon in tho wire3
{PG, LG lino3l:1. Reconnect the luel iniectorand IAC valve connectors.2. Measure voltage betweenbody ground and ECM/PCMconnector terminals 82, 810,820 and 822 individually.
B.pair open in the wiroltlb.twocn tho ECM/PCM .ndG101 lloc.t6d rt th. thormoiathouingl that had mo.e than 1 .0 V.
lsthere lessthan 1.0 V?
Chock for a shon in the wira3
{VCCI, VCC2 lin..l:Measure voltage between bodyground and ECM/PCN4 connectorterminals C19 and C28 individuallv.Chock lor a short in r s€nsor:While measuring voltagebetwoen body ground and ECM/PCM connector terminals C19and C28 individually, disconneclthe 3P connector ol each sensorone at time:
. TP sensor. Fueltank pressure sensor
ls there approx.5 V?
Rooair ahort in tho wire b€twoentho MAP sen3or. TP sensor, Fuel
tank Dreaaure Sonsor and theECM/PCM tC19, C28).
ls there approx. 5 V?
Sub3lhuio . known-good ECM/PCM .nd rcch6ck. lf tymptom/indic.tion go.3 away, rapl.ceth. original ECM/PCM.Replece the ronsor thtt hadapprox. 5 V.
(From page 11-86)
lcont'd)
r
28
I1011't317
19202123
vXv) iiP2rELlBLK)
IGPl(YEL/BLK)
ECM/FCM CONNECTOR A {25PI
Wire side of lemale terminals
(YEL/RED)
Wire side oflemale terminals
ECM/PCM CONNECTOR C {3'IP}
| 2i37Es/'t61718 192021\22
26272elE30 31
vcc2(YEL/BLUIktvccl
11-47
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PGM-FI System
Fuel Supply System
[POliil The"""ntool indicates Diagnostic Troubte Code (DTC) p0'171:Thefuet system istoo lean.
[Fo17ZJ rh""""ntool indicates Diagnostic Troubte code {DTc) p0172:Thefuel svstem istoorich.
Description
By monitoring the Long Term Fuel rrim, long term malfunctions in the fuel system will be detected.lf a malfunction has been detected during two consecutive trips, the MIL will come on and DTc p0171 and/or pol72 will bestored.
NOTE: lf someof the DTCS listed below are stored atthesametimeas DTC P017'l and/or p0172, troubleshoot those DTcsfirst, then troubleshoot DTC P0171 and/or PO1i2.
P0107, P0108, P1128, P'1129: MAP Sensor
P0135: Primary HO2S (Sensor 1)Heater
P0137, P0138: Secondary HO2S {Sensor 2)P0141: Secondary H02S (Sensor 2) Heater
P0441*r: EVAP System lnsufficient Purge FtowP1456*,, P'l457 *?i EVAP System Insufficient purge Ftow
Possible Cause
DTC P0171
too lean
*1: '97 model*2: '98 - 00 models
Fuel Pump insufficient flow/pressure
Fuel Feed Line clogged. leaking
Fuel Pressure Regulator stuck openFuel Filter clogged
Fuel Injector clogged, air leakage
Gasoline doesn't meet Owner's Manual spec.Primary HO2S (Sensor 1) deteriorated
Valve Clearance
Exhaust leak
Fuel Pressure Regulator clogged, stuck closedFuel Return Pipe clogged
Fuel Injector leaking
Gasoline doesn't meet Owner's Manual spec.Primary H02S (Sensor 1) deteriorated
EVAP Purge Control Solenoid Valve leaking, stuck openedValve Clearance
DTC P0172
flch
11-124
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Troubleshooting Flowchart
- The MIL has been rePorted on- DTC P0171 andlot P0172 are
stored,
Check the lu6l pressuro regulator
and tusl relum PiPe.ls the lLrel pressure too high
Check lhe Primaty HO2S:1. Start the engine. Hold the
engine at 3,000 rpm with no
load (in Park ot neutral) until
the radiator fan comes on
2. Check the Primary HO2S(Sensor 1) outPut with the
scan tool.
Check lh€ fuel pumP. fuel faedpipe. fuel fiher, and luel Prossurc.eguhior.
Does it stay at lessthan 0.3 V
or more than 0.6 V?
Check for a sticking or leaking
EVAP purge control solenoid
With a vacuum pump, aPPIY vacu
um to the EVAP Purge control
solenoid valve from the intake
manifold side.
Does it hold vacuum?
Check th6 valve clearanc€s and
adjust il necessary. It the valv€
clearances are OK, replace the
fuel iniectors.
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PGM-FI System
Random Misfire
lF()gool", tftod-' and some or lpiogol throughTo3oti
The scan tool indicates Diagnostic Trouble Code (DTC)
P0300*,, P1300*1 and some of po30t - pO3O4; Randommisfire.
Descriotion
Misfire detection is accomplished by monitoring the crankshaft speed with the crankshaft speed fluctuation (cKF) sensorwhich is attached to the crankshaft.lfmisfiring strong enough to damage the catalyst is detected, the MIL will blink during the time of its occurrence, and DTcP0300*', P1300*1 and some of DTCs P03ol through P0304 will be stored. Then, after misfire has ceased, the MtL will comeon,
lf misfiring that increases emissions is detected during two consecutive driving cycles, the MIL will come on, and DTcand some of DTCS p0301 through p0304 wi

be stored.NOTE: lf some of the DTCS listed below are stored at the same time as a misfire DTc, troubleshoot those DTcs first. thentroubleshoot the misfire DTC.
P0106, P]128, P1'129; MAp sensorP0171. P0172; Fuet metering
P0505: ldle Control Svstem
P1336, P1337; CKF sensor
P1361, P1362: TDC sensor
Pl381. Pl382: CYP sensor
P1508: IAC valve *1:,97 model*2: '98 - 00 models
Possiblo Caus€
. Fuel pump insufficient fuel pressure, amountofflow. Fuel line clogging. blockage, leakage. Fuel filter clogginga Fuel pressure regulator stuck open. Distributormalfunction
. lgnition coil wire open, leakage. lgnition control module malfunction. Valves carbon deposita Compression lowa Fuel does not meet Owner's Manual spec., lack offuel
Troubleshooting
By test-driving, determine the conditions during which misfire occurs. Depending on these conditions, test in the orderdescribed in the table below.
Possible cause
[ ;;;;- -....
Crankshaft
speed fluctuation
sensor
Fuel
pressureDistributor and
lgnition wirestcMValve
Clearance
Conditionsection 611-178section 23section 23section 6
Only low rpm and load,6)o
Only acceleratingooo
Only high rpm and loado@,a'@
Not specificationG\o@o@
NOTE: lf misfire doesn't recur, some possible causes are fuel that doesn't meet owner's manual spec, lack of fuel, carbondeposits on spark plu9, etc.
11-126
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Fuel Injectors
R6placomoni
1. Relieve the fuel pressure (see page 11-178).
2. Remove the resonato. chamber ('99 - 00 models).
O.RINGBeplace.
Disconnect the connectors from the fuel injectors, and disconnect the IAT sensor 2P connector ('97 - 98 models) and
EVAP purge control solenoid valve 2P conn€ctor ('97 - 98 models),
Disconnect the PCV valve and the vacuum hose from the fuel pressure regulator.
Place a shop towel over the fuel return hose, then disconnect it from the fuel pressure regulator.
Remove the retainer nuts on the fuel rail.
Disconnect the fuel rail.
7, Remove the fuel injectors from the intake manifold.
'97 - 98 model3:
EVAP PURGE CONTROLSOLENOID VALVE 2P CONNECTORIAT SENSOR
FUEL PULSATION2P CONNECTOR
12 N.m{1.2 kgt'm,8.7 tbtft)
FUELPRESSUREREGULATOR
O.RING
FUELPRESSUREREGULATOR
CUSHION
O.RINGReplace.
CUSHIONRINGReplace.
SEALRINGReplace.
Replace.
SEALRINGReplace.
S
11-179
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Fuel Supply System
Fuel Injectors {cont'dl
8. Slide new cushion rings onto the fuel injectors.
9, Coat newO-ringswith clean engine oil,and putthem onthefuel iniectors.
'10. lnsert the fuel injectors into the fuel rail first.
11. Coatnewseal ringswithclean engineoil,and press them into the intake manifold
12. To prevent damage to the O-rings, install the fuel injectors in the fuel rail first, then install them in the intake mani-
fold.
FUEL RAIL
The ill!stration shows'97 -98 models,'99 - 00 modelsare similar.
13. lnstall and tighten the retainer nuts.
14. Connect the vacuum hoses and fuel return hose to the fuel pressure regulator.
15. Connect the PCV valve.
16. Connect the connectors to the fuel injectors, the IAT sensor ('97 - 98 models), and the EVAP purge control solenoid
valve {'97 - 98 models).
Coat a new O-ring with clean engine oil, and install the resonator chamber ('99 - 00 models).
Turn the ignition switch ON (ll), but do not operate the starter. After the fuel pump runs for approximately two seconds,
the fuef pressure in the fuel line rises. Repeat this two or three times, then check whether there is any fuel leakage.
11.
18.
1 1-180
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EVAP PURGE CONTROL SOLENOID VALVE DUTY CONTROLLED AFTER
STARTING ENGINE
ENGINE COOLANT TEMPERATURE ABOVE 154"F (68'C)
Evaporative Emission (EVAP) Controls
Description:
The evaporative emission controls are designed to minimize the amount of fuel vapor escaping to the atmosphere. The
system consists of the following components:
A. Evaporative Emission (EVAPI Control Canister
An EVAP control canister is used for the temporary storage of fuel vapor until the luel vapor can be purged from the
EVAP control canister into the enqine and burned.
B. Vapor Purge ConirolSystem
EVAP control canister purging is accomplished by drawing fresh air through the EVAP control canister and into a pon
on the intake manifold. The purging vacuum is controlled by the EVAP purge control solenoid valve.
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 ot fuel vapor to the EVAP control canister.
'97 model:
EVAPPURGECONTROL
VALVEFromNo. 15BLK/ /ALTERNATORYEL I sP SENSOR r7.s At(in the under-dashfuse/relay box)
VARIOUSSENSORFEESH AIF
BLK
I
FUEI- TANK
(cont'd)
11-203
INTAKE MANIFOLD
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Emission Control System
Evaporative Emission (EVAP) Controls (cont'd)
99 - 00 models:
The scan tool indicates Diagnostic Trouble Code {DTC) P0451: The Fuel Tank Pressure sensor circuit range/oerformance Droblem.
ECM/PCM CONNECTORS
SG2 {GRN/BLK)
Wire side of {emaleterminals
FUEL TANKPRESSURESENSOR
VACUUMPUMP/GAUGE.0 -30 in.H9A973X - 041 -
XXXXX
- The MIL har been rooort€d on.- DTC P0451 b storod.
Check lor th6 tu6l tank pr€ssurelen30r:1. Do the ECM/PCM Reset Proce,oure.2. Remove the fuelfill cap.3. Turn the ignition switch ON (ll).4. Monitor the FTP Sensor voltage with the Honda PGMTester, or measure voltagebetween ECM/PCM connectorterminals A29 and C18.
Chock tho vacuum lin6s torrGlriction o. blockago repair asnecessary. lf OK, roplace the fueltank Drer3ur€ sentor.
ls there approx. 2.5 V?
Check for the fuel tank piessureSensot:L Disconnect the hose betweenthe EVAP two way valve andthe fuel tank pressure sensor atthe EVAP two way valve end.2. Connect a vacuum pump tothe open end ofthat hose.3. Turn the ignition switch ON (lll.4. Monitor the FTP S€nsor volt-age with the Honda PGMTester, or measure voltagebetween ECNI/PCNI connectorterminals A29 and C18, andcarefully appiy vacuum on thehose one stroke at a time.5. The voltage should smoothlydrop from the staning approx.2.5 V down to approx. 1.5 V.STOP applying vacuum whenthe voltage drops to approx.1.5 V or damage to the tueltank pressure sensor may
Does the voltage drop to approx.1.5 V and hold?
Intermittent tailuro. sv3tem is OKat this tim€. Chack to. poor con-n€ction6 or 10036 hose at fu6ltank pres3ure ionsor and fueltrnk.
a t32Pl
PTANK ILT GRNI
WAY VALVE
11-208
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