1997 HONDA CR-V Fuel injector

Fuel Cut-off Control
. During deceleration with the throttle valve closed, current to the fuel injectors iscutoffto improvefuel economyat
speeds over 970 rpm ('97 - 98 models), 920 rpm ('99 - 00 modelsl.
. Fuel cut-off action also takes place when engine speed exceeds 6,500 rpm ('97 - 98 models), 6900 rpm ('99 - 00
models), regardless of the position of the throttle valve, to protect the engine from over-rewing.
With Ay'T model. the PCM cuts the fuel at engine speeds over 5,000 rpm when the vehicle is not moving.*'
4,./C Comoressor Clutch Relav
When the ECM/PCM receives a demand for cooling from the air conditioning system, it delays the compressor from
being energized, and enriches the mixture to assure a smooth transition to the Ay'C mode.
Evaporative Emission (EVAP) Purge Control Solenoid Valve
When the engine coolant temperature is above 154"F (68'C), the ECM/PCM controls the EVAP purge control solenoid
valve which controls vacuum to the EVAP purge control canister,
Alternator Control
The system controls the voltage generated at the alternator in accordance with the electrical load and driving mode.
which reduces the engine load to improve the fuel economy.
PCM Fail-saf e/Back-up Functions
1. Fail-safe Function
When an abnormality occurs in a signal from a sensor, the ECM/PCM ignores that signal and assumes a pre-pre
grammed value for that sensor that allows the engine to continue to run.
2. Back-up Function
When an abnormality occurs in the ECM/PCM itself, the fuel injectors are controlled by a back-up circuit independent
of the system in order to permit minimal driving.
3. Self-diagnosis Function IMalfunction Indicator Lamp (MlL)l
When an abnormality occurs in a signal from a sensor, the ECM/PCM supplies ground for the MIL and stores the DTC
in erasable memory. When the ignition is initially turned on {ll), the ECM/PCM supplies ground for the MIL for two
seconds to check the MIL bulb condition.
4. Two Trio Detection Method
To prevent false indications, the Two Trip Detection Method is used for the HO2S*1, fuel metering-related. idle control
system, ECT sensor and EVAP control system self-diagnostic functions. When an abnormality occurs, the ECM/PCM
stores it in its memory. When the same abnormality recurs after the ignition switch is turned OFF and ON (ll) again,
the ECM/PCM informs the driver by lighting the MlL. However, to ease troubleshooting, this function is cancelled
when you jump the service check connector, The MIL will then blink immediately when an abnormality occurs.
5. Two (or Three) Driving Cycle Detection Method {'97 model)
A "Driving Cycle" consists of starting the engine, beginning closed loop operation, and stopping the engine. lf misfir-
ing that increases emissions or EVAP control system malfunction is detected during two consecutive driving cycles.
or TWC deterioration is detected during three consecutive driving cycles, the ECM/PCM turns the MIL on. However, to
ease troubleshooting, this function is cancelled when you jump the service check connector. The MIL will then blink
immediately when an abnormality occurs.
*1: '97 - 98 models*2: '99 - 00 models
5.
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(From page 11-84)
Reolace the Sensor that causedthe lighl lo go out.Does the MIL go off.,
Check for a short in the wires
lvCC linesl:1. Turn the ignition switch oFF.2. Disconnect the PCM connector D (16P).
3. Check for continuity betweenbody ground and PCM connector terminals D4 and Dl0 individually.
Repair shorl lo body ground
in the wile between the PCM
{D4} and the MAP sensor.Repair short to body ground inth€ wire between the PCMlol0l and the TP sensor.
Check tor an open in the wires
llGP line3l:1. Disconnect the fuel injectorconnectors and IAC valve con
2. Turn the ignition switch ON (lli.
3. [,4easure voltage betweenbody ground and PCM con'nector terminals A'11 and A24individually.- Repair open in the wire(slboiween the PCM 1A11, A24)and the PGM-Fl main relav.- Ch€ck lor poor connectionsor loose wires at ihe PGM-FImain relay.- Tesi lhe PGM-FI main relav
{see p.g6 1l-1871.Check for an open in the wires
{LG linesl:1. Turn the ignition switch OFF.2, Reconnect all sensor connec-tors,3. Reconnect the PCM connectorD (16P).
4. Turn the ignition switch ON (ll).
5, M easu re voltage betweenbody ground and PCM connector terminals Ag a^d 422individually.
R6pair open in the wire{slbetween the PCM {A9. A22l andG101 {located at the thetmostathousing) that had more than 1.0 V.
ls there less than 1.0 V?
Substituto a known-good PCMand rech€ck. It symptom/indica-tion goos away, replace the origi-nal PCM.
PCM CONNECTOR D (16PI
VCCl NEL/RED}
Wire side of female terminals
PCM CONNECTOR A (32PI
Wire side of lemale terminals
1 1-85
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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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Misfire Detected in One Cylinder
Ipffi1] Thescantoot indicates Diagnostic Trouble Code (DTC) P0301: Cylinder 1 misfire detected.
lF03O2l 16".""n toot indicates Diagnostic Trouble Code (DTC) P0302; Cylinder 2 misfire detected.
I P0303 | fne scan tool indicates Diagnostic Trouble Code (DTC) P0303: Cylinder3 misfire detected.
lF0il04l 16" ""un tool indicates Diagnostic Trouble Code (DTC) PO3O4: Cylinder 4 misfire detected
Description
Misfire detection is accomplished by monitoring the crankshaft speed with the crankshaft speed fluctuation (CKF) sensor
which is attached to the crankshaft.
lf misiiring strong enough to damage the catalyst is detected, the MIL will blink during the time of its occurrence. and DTC
P0301, P0302, P0303 and/or P0304 will be stored. Then, after the misfire has ceased, the MIL will come on.
lf misfiring that increases emissions is detected during two consecutive driving cycles. the MIL will come on, and DTc
P0301, P0302, P0303 and/or P0304 will be stored.
NOTE: lJ some of the DTcs listed below are stored at the same time as a misfire DTc, troubleshoot those DTcs first, then
troubleshoot the misfire DTC.
P0107, P0108, P'n2a, P1129t MAP sensor
Po'17 'l , P0112t Fuel suPP|Y system
P0441: EVAP insufficient Purge flow
P1336, P1337: CKF sensor
P1359, Pl361, P1362: TDC sensor
Pl381, P1382: CYP sensor
Possible Cause
. Fuel injector clogging, fuel leakage, air leakage
. Fuel injector circuit open or shorted
. Spark plug carbon deposits, fouling, malfunction
. lgnition wires open, leaking
. Distributor malfunction
. Compression low
. Valve clearance out of specification
(cont'd)
11-127
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(From page 11-128)
lntormittent misfire due lo sparkplug fouling, etc. (no mislire at
this tim€).
ls DTC P0301, P0302, P0303,or P0304 indicated?
ooes the misfire occur in theother cylinder?Replace the faulty spark Plug.
Check lor fuel iniector maltunc-
t|on:1. Exchange the fuel injectorfrom the problem cylinderwith one from another cylin-der.2. Let the engine idle for two min
utes.3. Test'drive the vehicle severaltimes in the range of the freezedata,
lntermittent misfiro due lo bad
contrct in the fuel iniector con-nector {no misfire at this time).
ls DTC P0301, P0302, P0303,or P0304 indicated?
Does the misfire occur in theother cylinder?Replace lhe faulty luel inlector.
Check following items- Valvo clearance- Cvlinder l€ak-down- Compression- Crsnkshaft Speed FluctuationICKF) sensol
NOTE: lf there is no freeze data of misfiring, test drives under various condi_
tions are necessary.
11-129
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Fuel Supply System
System Description
The fuel supply system consists of a fuel tank, in-tank
high-pressure fuel pump. PGM-Fl main relay, fuel filter,
fuel pressure regulator, fuel injectors, and fuel delivery
and return lines. This system delivers pressure-regulat-
ed fuel to the fuel injectors and cuts the fuel delivery
when the engine is not running.
Fuel Pressure
Relieving
Before disconnecting fuel pipes or hoses, release pres-
sure from the system by loosening the 12 mm banjo
bolt on the too of the fuel filter.
Do not smoke while working on the fuel system.
Ke€p open flames or sparks away from your work
area,
Be sure to relieve fuel pressure while the ignition
switch is off.
Write down the frequencies for the radio's preset
buttons.
Disconnect the battery negative cable from the bat-
tery negative terminal.
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 banjo bolt.
Slowly loosen the 12 mm banjo bolt one complete
rurn 12 mm BANJoBOLT
1.
SHOP TOWEL
NOTE: Replace the washers whenever the 12 mm
banio bolt is loosened or removed.
11-178
Inspection
1, Relieve fuel pressure.
2. Remove the 12 mm banjo bolt on the fuel filter while
holding the fuel filter with another wrench. Attach
the 12 mm fuel pressure adapter bolt and the special
tool.
FUEL PRESSUREREGULATON
FUELPRESSUREGAUGE07406 - 0040001
The illustration shows'97 - 98 models,'99 - 00 models are similar.
Start the engine. Measure the fuel pressure with the
engine idling and the vacuum hose of the fuel pres-
sure regulator disconnected from the fuel pressure
regulator and pinched. lf the 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.
Pressure should be:'97 - 98 mod€ls:
260 -31O kPa 12.7 - 3.2 kgf/cm,, 38 - 46 psil'99 - 0O models:
270 - 32O kPa Q.A - 3.2 kgf/cm', ifo - /U psil
Reconnect vacuum hose to the fuel pressure regulator.
Prgs3ure should be:'97 - 98 models:
210 - 25O kPa 12.1- 2.6 kgf/cm', 30 - 37 psi)'99 - 00 models:
22O -26iJ kPa 12.2 - 2.7 kgt/cm', 31 - 38 psi)
lf the fuel pressure is not as specified, first check the
fuel pump (see page 11- 183). lf the fuel pump is OK,
check the 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-
181).
. lf the fuel pressure is lower than specified. inspect
for:- Clogged fuel filter.- Faulty fuel pressure regulator (see page 11-
1811.- Fuel line leakage.
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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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