Intake air control valve HONDA CR-V 1997 RD1-RD3 / 1.G Workshop Manual

13. Remove the upper radiator hose, heater hose and
water bypass hose.
WATER BYPASS
UPPEBRADIATORHOSE
17
HEATERHOSE
Remove the engine wire harness connectors and
wire harness clamps from the cylinder head and the
intake manifold.
o Four fuel injector connectors
. Engine coolant temperature (ECT) sensor con-
neclor
. Radiator fan switch connector
. Coolant temperature gauge sendlng unlt connec-
tor
. Throttle position sensor connector
. Manifold absolute pressure {MAP) sensor con-
nector
Primary heated oxygen sensor (primary HO2S)
connector
ldle air control (lAC) valve connector
Distributor connector
Remove the spark plug caps and distributor from the
cylinder head.
Remove the cruise control actuator (see section 4).
Support the engine with a jack, then remove the
upper bracket. Make sure to place a cushion
between the oil pan and the iack (see page 6-10).
a
18. Remove the cylinder head cover.
19. Inspect the timing belt (see page 6-9).
CYLINDER
(cont'd)
6-19
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Fuel and Emissions
Special Tools ...................... 11-2
Component Locations
lndex ...................... ....,.... 11-3
Svstem Description
Vacuum Connections ...........,....,.,................. 1 1-9
Electrical Connections ................................... 1 1-15
System Connectors .,.,,.,............................,.,. 1 1-36
Troubleshooting
Troubleshooting Procedures,.,..................... 11-60
Engine Control Module/Powertrain ConttolModule Terminal Arrangement .............., 11-67
Diagnostic Trouble Code Chart .................... 1 t-75
How to Read Flowcharts .......,.....,.,............... I 1-79
PGM-Fl System
System Description .................,.,.,,,............... 1 1-80
Troubleshooting Flowcharts
Engine Control Module/PowertrainControl Module ........11-52
Manifold Absolute Pressure Sensor ............. 11-90
Intake Air Temperature Sensor .................... 1 1-95
Engine Coolant Temperature Sensor .,..,.,.... 1 1-99
Throttle Position Sensor ...........,.....,.,.,..,...... I 1'103
Primary Heated Orygen Sensor (Sensor 1) ... 11-110
Secondary Heated Oxygen Sensor{Sensor 2l .................. 1 1-117
Heated Oxygen Sensor Heater ..................... 11-121
Fuef Supply System ......11-124
Random Misfire ,....,.,..... 11-126
Mistire Detected in One Cylinder .....-........... 11-128
Knock Sensor ................ 11-130
CKP/TDC/CYP Sensor .................................... 1 1-131
Vehicle Speed Sensor ...............................,.... 1 1-135
Barometric Pressure Sensor .....,...,...,.,,........ 1 1-137
Electrical Load Detector ...,.,.......................... 1 1-138
CKF Sensor ................,.,, '11-112
ECM/PCM lnternaf Circuit ............................. 11'117
HO2S Replacement .,.,.,. 11-148
ldle Control System
System Description ............ 11-149
Troubleshooting Flowcharts
ldle Control System ...... 11-150
fdle Air Control Valve ......................,............. 11-152
Air Conditioning Signal ................................. I 1-155
Alternator FR Signal ...................................... 1 1-159
Starter Switch Si9na1 .................................... t l-161
Power Steering Pressure Switch Signal ...... 11-162
Brake Switch Si9na1 ...................................... 11-166
Fast ldle Thermo Valve .,.,.............................,.,.,. 11-168
ldle speed setting .............. 11-169
Fuel Supply System
Fuel Lines ............................ 11-171
Fuef Tube/Ouick-Conneci Fittings ..................... 11 -175
System Description ............ 11-178
Fuel Pressurg ...................... 11-178
Fuel Iniectors ................,..... 11-179
Fuel Pressure Re9u1ator .............................,.,...., f 1-181
Fuef Fifter ....,.,.,.,,,,.,............11-142
Fuel Pump ........................... 11-183
Fuel Gauge .......................... 11-184
Fuel Gauge Sending Unit ................................... I 1-185
Low Fuel Indicator System ...........,.,..,............... 1 1-185
PGM-FI Main Relay ............. 11-187
Fue|Tank................ ............. 11-191
Intake Air System
System Description ............ 11-193
Air Cleanel ,.,.,..................... 11-194
Throttle Cable ..................... 11-194
Throttle Body........ .............. 11-196
Emission Control System
System D$cription ...,....,.,. 11-199
Tailpipe Emission ............... 11-199
Three Way Catalytic Converter ..................,.,...,, 11-199
Positive Crankcase Ventilation System .,.,,,,.,.., 11-2O1
Evaporative Emission Controls .........,.,.,............ 11-203
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Component Locations
lndex
'97 - 98 models:
MANIFOLD ABSOLUTEPRESSURE IMAP} SENSORTroubleshooting, Page 1 1-90
THROTTLE POSITION (TP}
SENSORTroubleshooting, page 1 1-103
toLE AtR CONTROL llAcl VAI-VE
Troubleshooting, page 1 1-152
EVAPORATIVE EMISSION (EVAP)
CONTROL CANISTER VENT SHUTVALVE t'98 mod€llTroubleshooting, page 11'213
INTAKE AIR TEMPERATUREIIATI SENSORTroubleshooting. page 1 'l -95
ELECTRICAL LOADDETECTOR IELD) (USA modol)Troubleshooting, page 1 1-138
VEHICLE SPEEDSENSOR (VSS)
Troubleshooting,page 11'135
CRANKSHAFTPOSTTtON/
POWER STEERING PRESSURElPsPl swtrcHTroubloshooting, page 1 1-162
TOP OEAD CENTER/CYLINDERPOStTtON{CKP/TDC/CYP} SENSOR(Built into the distributor)Troubleshooting, page 1 l-131
CMNKSHAFT SPEEDFLUCTUATION ICKF} SENSORTroubleshooting. page 1'!-142
ENGINE COOLANTTEMPERATUREIECTI SENSORTroubleshooting, page 11 99
EVAPORATIVEI€VAP) PURGE CONTROLSOLENOID VALVETroubf eshooting, page 1 1'2o5, 213
(cont'd)
11-3
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Component Locations
Index (cont'dl
39 - 00 models:
MANIFOLD ABSOLUTEPRESSURE IMAPISENSORTroubleshooting, page 1 1-90
THROTTLE POSITION {TP)SENSORTroubleshooting, page 1 1-103
IDLE AIR CONTROL OACI VALVETroubleshooting, page 1 1-152
EVAPOBATIVE EMISSION {EVAPICONTROL CANISTER VENT SHUTVALVETroubleshooting, page 1 1-213
EVAPORATIVE EMISSION(EVAPI PURGE CONTROI-SOLENOID VALVETroubleshootang, page 1 1-2'13
ELECTRICAL LOAOOETECTOR {ELD) IUSA modet)Troubleshooting, page I 1-138
INTAKE AIR TEMPERATURE(IAT) SENSORTroubleshooting, page 11 95
POWEB STEERING PRESSUREtPsPt swtTcHTroubleshooting, page 11 162VEHICLE SPEEDSENSOR IVSSITroubleshooting,page 11'135
CRANKSHAFTPOSTTTON/TOP OEAD CENTER/CYLINDERPOStTtON{CKP/TDC/CYP) SENSOR(Built into the distributor)Troubleshooting, page 11 131
CRANKSHAFT SPEEDFLUCTUATION ICKN SENSORTroubleshooting, page 1 1-142
SENSORTroubleshooting, page '11 130
ENGINE COOLANTTEMPERATURE{ECT)SENSORTroubleshooting, page 11 99
11-4
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System Description
Vacuum Connections (cont'dl
'97 model:
ENGINECOOLANT
ITr|ll
O PRIMARY HEATED oxYGEN sENsoR {PRIMARY Ho2s,SENSOR lt
O SECONDARY HEATED oxYGEN sENsoR {SECoNDARYHO2S. SENSOR 2l€) MANIFOLD ABSOLUTE PRESSURE (MAPI SENSOR@ ENGINE cooLANT TEMPERATURE {EcT} sENsoRO INTAKE AIR TEMPERATURE (IAI} sENsoR@ CRANKSHAFT SPEED FLUCTUATION ICKFI SENSORO |DLE ArR coNTRoL {tAc)vALvE@ FAST IDLE THERMo vALvEO THRoTTLE EoDY ITB)@ FUEL INJEcTonO FUEL PULSATIoN oAMPER@ FUEL FILTEn(} FUEL PRESSURE REGULATOR
FUEL PUMPFUEL TANKFUEL TANK EVAPORATIVE EMISSION (EVAPIVALVEAIR CLEANERRESONATORPOSITIVE CRANKCASE VENTILATION {PCVI VALVEEVAPORATIVE EMISSION {EVAP} PURGE CONTROLSOI.'ENOID VALVEEVAPORATIVE EMISSION {EVAP) CONTROL CANISTEREVAPORATIVE EMISSION {EVAPI TWO WAY VALVETHREE WAY CATALYTIC CONVERTER (TWC)
@(D(D
o@(}
@
@@@
1 1-10
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System Description
I
I
I
Vacuum Connections (cont'dl
'98 model:
C PRIMARY HEATEO OXYGEN SENSOR (PRIMARY HO2S,
SENSOR 1)(, SECONDARY HEATEO OXYGEN SENSOR ISECONDARYHO2S, SENSOR 2)(!)\\\\ss\SNBSS\\\ETRESS\RE\\NQ\SE\SSR
G) ENGINE COOLANT TEMPERATUBE (ECT) SENSOR
O INTAKE AIR TEMPERATURE {IAT} SENSOR
@ CRANKSHAFT SPEED FLUCTUATION (CKFI SENSOR
O IDLE AIR CONTROL (IAC) VALVE
@ FAST IDLE THERMO VALVE (A/T)
O THROTTLE BODY (TBI(0) FUEL INJECTOR.1' FUEL PULSATION DAMPER.14 FUEL FILTER(i FUEL PRESSURE REGULATOR14 FUEL PUMP(D FUEL TANK@ FUEL TANK EVAPORATIVE EMISSION {EVAPI VALVE
C] AIR CLEANER(O RESONATOR1iC POSITIVE CRANKCASE VENTILATION (PCV) VALVE
6 \$REE$IN gN NL$\C CON\ER\ER (TNC\
ti q rpos,xr E qN
ssros \E aP cqN\RoLcaNtsr€R
@ EVAPORATIVE EMISSION IEVAP) PURGE CONTROL
SOLENOID VALVEq3 EVAPORATIVE EMISSTON IEVAP} CONTROL CANISTER
VENT SHUT VALVE
@ EVAPORATIVE EMISSION (EVAP) TWO WAY VALVE
€i EVAPORATIVE EMISSION {EVAP) BYPASS SOLENOID
VALVE
€9 FUEL TANK PRESSURE SENSOROi EVAPORATIVE EMISSION {EVAP) THREE WAY VALVE
Qd PURGE JOINT
G/T only)
f
-i*'";-t
COOLANT Jt
U
11-12
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System Description
Vacuum Connections (cont'dl
'99 - q) models:
ENGINECOOLANT
t
o
o
o@
o@@@@@@@@@(t
PRIMARY HEATED OXYGEN SENSOR IPRIMARY HO2S,SENSOR 1lSECONDARY HEATED OXYGEN SENSOR {SECONDARYHO2S. SENSOR 2lMANIFOLD ABSOLUTE PRESSURE (MAPI SENSORENGINE COOLANT TEMPERATURE IECN SENSORINTAKE AIR TEMPERATURE IIATI SENSORCRANKSHAFT SPEED FLUCTUATION {CKF) SENSORKNOCK SENSOR (KS}
IDLE AIR CONTROL IIACI VALVEFAST IDLE THERMO VALVE {A/T}THROTTLE BODY (TB}
FUEL INJECTORFUEL PULSATION DAMPERFUEL FILTERFUEL PRESSURE REGULATORFUEL PUMPFUEL TANKFUEL TANK EVAPORATIVE EMISSION (EVAPI VALVE
AIR CLEANERRESONATORPOSITIVE CRANKCASE VENTILATION (PCV} VALVETHREE WAY CATALYTIC CONVERTER ITWCIEVAPORATIVE EMISSION {EVAPI CONTROL CANISTEREVAPORATIVE EMISSION IEVAPI PURGE CONTROLSOLENOID VALVEEVAPORATIVE EMISSION {EVAPI CONTROL CANISTEFVENT SHUT VALVEEVAPORATIVE EMISSION IEVAPI TWO WAY VALVEEVAPONANVE EMISSION {EVAPI AYPASS SOLENOIDVALVEFUEL TANK PRESSURE SENSOBEVAPORATIVE EMISSION IEVAPI THREE WAY VALVEPURGE JOINT
@@@@@@
@
@@
@@@
11-14
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Troubleshooting
Troubleshooting Procedures (cont'dl
Symptom Chart
Listed below are symptoms and probable causes for problems that DO NOT cause the Malfunction Indicator Lamp (MlL) tocome on. lf the MIL was reported on, go to page 11-60.Troubleshoot each probable cause in the order listed (from left to right) until the symptom is eliminated,The probable cause and troubleshooting page reference can be found below.
Other Probable Causes for an engine that will not start:- Compression- Intake air leakage- Engine locked up- Timing belt- Starting system- Overheating- Battery
SYMPTOMPROBABLE CAUSE
Engine will not sta rt4, 2,3,5,20, 't5, 1
Hard starting2, 4, 12,17, 14, 't9
Cold fast idle too low7, a,9, 6, 17
Cold fast idle too high7,8,9,11,10
ldle speed fluctuates9,7,8, 't1, 10
Misfire or rough runningTroubleshoot for misfire on pages '11-126, 1|21LOl/\/ power2, 10,11, 13, '17, 18,20
Engine stalls2, 4, 12,1,20,9,5, 't6
Probable Cause List (For the DTC Ch8rt, see page ll-75.)
Probable CausePageSystem
Engine controt ruoaute (ecvtffi'I11-42
I 1-178Fuel oressure
PGM-Fl main relav
lgnition system
Crankshatt Position/Top Dead Center/Cylinder position sensor circuit
Intake Air Temperature (lAT) sensor ctrculr
ldle Air Control (lAC) Vatve
Fast idle thermo valve
ldle speed adjustment
Throttle body
Throftle cable
Manifold Absolute P."""rr"ffi
Throftle Position (TP) sensor
Barometric pressur" (gnno-
Ay'T gear position signal
Brake switch signal
Air Cleaner
Three Way Catalytic Converter (TWC)
Evaporative emission (EVAP) control
Contaminated fuel
1 1- 187
Section 4
5't1-'t31,146
6I 't-95
711-152
81'l-168
1 1- 169
1011-196'1111-'194
12'1 'l -90
1 1- 103
1411-137
15Section 14
161 1- 166
17r 1-194
181 1,199'1911-203
20
11-64
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Troubleshooting
Troubleshooting Procedures (cont'd)
DataDescliptionOperating ValueFreezo Data
HO2S
Feedback
Loop Status
Loop status is indicated as "open" or "closed".
Closed: Based on the HO2S output, the ECM/pCM deter-mines the airlfuel ratio and controls the amount ofinjected fuel.
Open: ignoring HO2S output, the ECM/pCiM refers to sig,nals from the TP, MAP, and ECT sensors to control theamount of injected fuel.
At idle speed: closed
YES
Short Term
Fuel Trim
The airlfuel ratio correction coefficient for correcting theamount of injected fuel when HO2S feedback is in theclosed loop status. When the signal from the HO2S isweak, short term fuel trim gets higher, and the ECM/PCMincreases the amount of injected fuel. The airlfuel ratiogradually gets richer, causing a higher HO2S output.Consequently. the short term fuel trim is lowered. andthe ECM/PCM reduces the amount of injected fuel.This cycle keeps the airfuel ratio close to the stoichio-metric ratio when in closed looD status.
t:20y"
YES
Long Term
Fuel Trim
Long term fuel trim is computed from shon term fueltrim and indicates changes occuring in the fuel supplysystem over a long period.
lf long term fuel trim is higher than 1,00. the amount ofinjected fuel must be increased. lf it is lower than L00.the amount of injected fuel must be reduced.
! 20%
Intake Air
Temperature
(IAT)
The IAT sensor converts intake air temperature into volt-age and signals the ECrU/PCM. When intake air tempera-ture is low, the internal resistance of the sensorincreases, and the voltage signal is higher.
With cold engine:
Same as ambient temper-
ature and ECTYES
Throttle
Position
Based on the accelerator pedal position, the openingangle of the throttle valve is indicateo.At idle speed:
approx. 10%
lgnition
Timing
lgnition timing is the ignition advance angle set by theECM/PCM. The ECM/PCM matches ignition timing to thedriving conditions.
At idle speed: 16'1 4.
BTDC with the SCS ser-
vtce connector connected.
NO
Calculated
Load Value(cLV)
CLV is the engine load calculated from the MAp data.At idle speed:
2A - 410/o
At 2,500 rpm with no load:
13 - 260/o
YES
_
1 1_66
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ldle Control System
System Description
The idle speed of the engjne is controlled by the ldle Air Control (lAC) Valve'
The valve changes the amount of air bypassing into the intake manifold in response to electric current controlled by the
ECM/PCM. When the lAc valve is activated, the valve opens to maintain the proper idle speed.
YEL/ From PGM'FI
BLK TMAIN RELAY
VARIOUSSENSORS
4.
IAC VALVE
INTAKE MANIFOLD
After the engine starts, the IAC valve opens for a certain time. The amount of air is increased to raise the idle speed
about 150 - 300 rpm.
when the cootant temperature ts row, the lAc valve is opened to obtain the proper fast idle speed The amount o{
bvoassed air is thus controlled in relation to the engine coolant temperature
When the idle speed is out o{ specification and the scan tool does not indicate Diagnostic Trouble Code (DTC) P0505
or P1508, check the following items:
. Adjust the idle speed (see page 11-169, 170)
. Air conditioning signal (seepagell-1551
. ALT FR signal (see page 1l-159)
. Starter switch signal (see page 11-16'1)
. A,/T gear position signal (see section 14)
. PSP switch signal (seepagell-162)
. Brake switch signal (see page 11-165)
. Fast idlethermovalve (see page'11 168)
. Hoses and connecttons. IAC valve and its mounting O-rings
lf the above items are normat, suDslitute a known-good IAC valve and readjust the idle speed {see page 11-169, 170)
lf the idle speed still cannot be adjusted to specification (and the scan tool does not indicate DTC P0505 or Pl508)
after IAC valve reolacement, substitute a known-good ECM/PCM and recheck lf symptom goes away' replace the
original ECM/PCM.
11-149
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