Intake manifold HONDA CR-V 1999 RD1-RD3 / 1.G Owner's Manual

ldle Control System
ldle Air Control llAC) Valve
The scan tool indicates Diagnostic Trouble Code (DTC) Pl508: A probtem in the ldle Air Controt flAC) varvecircuit.
The IAC Valve changes the amount of air bypassing the throttle body in response to a current signal from the ECM/PCM inorder to maintain the proper idle speed.
37 model;
IAC VALVE 2P CONNECTOR {C132}
,f rcp'# IYEL/BI.(II2f-1-d)
Y
Wir€ side of female terminals
PCM CONNECTOR A I32PI
tacvIBLK/BLU)
From AIR To INTAKECLEANER MANIFOLD
Wire side of female terminals
The MIL has beon .eport€d on.OIC Pl508 is sto.ed.
Problem veiification:1. Do the PCM Reset Procedure.2. Start the engine, and warm itup to normal operating tem-perature.
Inte.mittent failure, systcm b OKat thi3 time. Check tor poo. con-nections or loose wircs at C132(lAC v.lvel and at the PCM.
ls DTC Pl508 indicated?
Check lor an open in the wir6{lGPl lins}:1. Turn the ignition switch OFF.2. Disconnect the IAC valve 2Pconnector.3. Turn the ignition switch ON {ll).4. Measure voltage between bodyground and the IAC valve 2Pconnector term inal No.2.
Repair open in the wire trctwoontha IAC v!lv6 and the PGM-Flmain relly.
Chock for an opan o. short in thowi.e (lACv linel:1. Turn the ignition switch OFFand reconnect the IAC valve2P connector.2. Disconnect the PCM conneclorA (32P).
3. Turn the ignition switch ON {ll).4, Measure voltage betweenbody ground and PCM con-nector terminal A12.
{To page 1l-153)
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ldle Control System
Fast ldle Thermo Valve lA/T)
Description
To prevent erratic running when the engine is warming
up, it is necessary to raise the idle speed. The fast idle
thermo valve is controlled by a thermowax plunger.
When the engine is cold, the engine coolant surround-
ing the thermowax contracts the plunger, allowing addi-
tional air to be bvDassed into the intake manifold so that
the engine idles faster. When the engine reaches operat-
ing temperature. the valve closes, reducing the amount
of air bypassing into the intake manifold.
IDLEADJUSTING
IDLETHERMOVALVE
AIR BYPASS VALVE
11-168
Inspgction
NOTE: The fast idle thermo valve is factory adjusted; it
should not be disassembled.
1. Remove the intake air duct from the throttle body.
2. Start the engine,
3. Put your finger over the lower port in throttle body,
and make sure that there is air flow with the engine
cold (engine coolant temperature below 86"F, 30'C).
lf there is no air flow, replace the fast idle thermo
valve and retest,
O-RINGSReplace.
11.0 kgfl.m, 7.2 lbl.ftl
Start the engine. Hold the engine at 3,000 rpm with no
load (in Park or neutral) until the radiator fan comes
on, then let it idle.
Check that the valve is completely closed. lf the valve
is leaking, the idle speed will drop when you cover the
lower pon. Check the engine coolant level and for air
in the engine cooling system {see section 10). lf the
cooling system is OK, replace the fast idle thermo
valve and recheck.
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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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Intake Air System
System Description
The system supplies air for all engine needs. lt consists of the intake air pipe, Air Cleaner, intake air duct, Throttle Body
(TB), ldle Air Control (lAC) Valve, fast idle thermo valve, and intake manifold. A resonator in the intake air pipe provides
additional silencing as air is drawn into the system.
INTAKE MANIFOLD
YEL| - - Fiom PGM'FI
BLK T MAIN RELAY
IDLETHERMO
lJ- _iuo'u'j"'
INTAKEAIR DUCT
vaRtousSENSORS
FESONATON
THROTTLEBODY (TB)
1 1-193
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Positive Grankcase Ventilation (PGVI System
Description
The Positive Crankcase Ventilation (PCV) svstem 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 manitold vacuum and
the blow-by gas is drawn directly into the intake manifold.
-: BLOW.BY VAPOR-: FRESH AIR
i/lAlrllFOLD
Inspoction
1. Check the PCV hoses and connections for leaks and
clogging.
'97 - 98 models:
'99 - (X) models:
BREATHERHOSE
(cont'd)
11-201
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Emission Control System
Positive Crankcase Ventilation (PCV) System (cont'dl
2. At idle, make sure there is a clicking sound from the
PCV valve when the hose between the PCV valve
and intake manifold is lightly pinched with your fin-
gers or pliers.
'97 - 98 models:
'99 - 00 modelsi
lf there is no clicking sound, check the PCV valvegrocrmet for cracks or damage, lf the grommet is
OK, reDlace the PCV valve and recheck.
Gently pinch here.
Gently pinch here.
11-202
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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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