Idle valve HONDA CR-V 1997 RD1-RD3 / 1.G Owner's Manual

(From page 11-150)
{From page 11-150}
THERMO VALVE(A/T onlyl
Check the IAC valve:Disconnect the 2P connector from
the IAC valve.
Does the engine speed droP
or the engine stall?
Adiust the (basel idl€ speed lseepage 11-169, 1t0). Itihe ba3e idle
speed cannot be adiust€d, clean
the Dorts in the throttle body.
UPPER
Check the tast idle lhermo valve:
1. Turn the ignition switch OFF.
2. Remove the intake air ductfrom the throttle body.3. Start the engine and let it idle.
4. Put your finger on the lowerpon in the throttle body.
Check engine cool.nt level and for
air in the cooling sy3lem. lf OK,
reolace the f.st idle thermo valve.Does the engine speed drop?
Put your Iinger on the uPPer Portin the throttle body.
Check for vacuum leaks, make
sure the throttle valve is com'pletely clo3ed. and repair as nec-Does the engine speed droP?
Adjust the idle spoed lsee Page11-169. 1701. lf the adiustmentdoes not correct lhe problem,
r.olace the IAC valve.
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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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ldle Speed Setting
Inspoction/Adiustmont
37 modsl:
NOTE:
. Before setting the idle speed, check the following
items:- The MIL has not been reportsd on.- lgnition timing- Spark plugs
- Air cleaner- PCV system
. lcanada) Pull the parking brake lever up. Stan the
engine, then check that the headlights are off.
1. 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.
Connect a tachometer or a Honda PGM Tester.
Disconnect the 2P connector from the ldle Air Con-
trol (lAC) valve.
IAC VALVE
lf the engine stalls, restart the engine with the accel-
erator pedal slightly depr6ss6d, Stabilize the rpm at
1,000, then slowly release the pedal until the engine
idles.
Check idling in no-load conditions: hsadlights,
blower fan, rear d€fogger, radiator fan, and air con-
ditioner are not operating.
ldle spood should b.:
{80 t 50 rpm {in Park or noutr.ll
IDLE
7.
Adjust the idle sp6ed,
idle adjusting screw.
if necessary, by turning the
Turn the ignition switch OFF.
Reconnect the 2P connector to the IAC valve, then
remove the BACK UP (RAD|Ol (7.5 Al fuse in the
under-hood fuse/rslav box for 10 seconds to reset
the PCM.
Restart and let the engine idle with no-load condi-
tions for one minute, then check the idle speed.
NOTE: (Canadal Pullthe parking brake lever up. Stan
the engine, then check that the headlights are off.
ldlo Ep€ed rhould be:
75O t 50 rpm (in P.rk or noutr.ll
Let the engine idl6 for one minute with the head-
lights (Low) ON, and check th€ idl€ speed.
ldle lpcod 3hould bo:
750 t 50 ]pm (in Park or nautlal)
Turn the headlights off. Let th€ engine idle for one
minute with the headlights (Low) ON, heater fan
switch at Hl and air conditioner on. then check the idle
sDeeo.
ldl. specd should b6:
7d) 1 50 rpm {in Park or nautral}
lf the idle speed is not within specification, see the
symptom chart on page 11-64. (cont'd)
1 1-169
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ldle Control System
ldle Speed Setting (cont'd)
38 - 0O mod6l3:
NOTE: Before setting the idle speed, check the follow-
ing items:- The MIL has not been reported on.- lgnition timing- Spark plugs
- Air cleaner- PCV system
1. 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.
Connect a tachometer.
Disconnect the IAC valve 2P connector and the EVAP
purge control solenoid valve 2P connector.
CONTROLSOLENOID VALVE
SOLENOID VALVE
lf the engine stalls, restart the engine with the accel-
erato. pedal slightly depressed. Stabilize the rpm at
1,000, then slowly release the pedal until the engine
idles.
Che€k the idle in no-load conditions: headlights, blow-
er fan, rear defogger, radiator fan, and air conditioner
are not operating,
ldle speed should bo:
480 t 50 rpm {in PErk or noutrall
11-170
lf necessary, adjust the idle speed, by turning the
idle adjusting screw.
After adjusting the idle speed, recheck the ignition
timing (see section 4). lf it is out of spec, go back to
steo 4.tDt.E
6. Turn the ignition switch OFF.
7. Reconnect the 2P connectors to the IAC valve and
the EVAP purge control solenoid valve, then do the
ECM/PCM reset procedure.
8. Restart and idle the engine with no-load conditions
for one minute, then check the idle speed.
ldle speod should be:,98 model:
750 t 50 rpm tin Park or neutral)'9!l - 00 modsls:
730 i 50 lpm lin Psrk or neutral)
NOTE: lf the idle speed increases to 780 t 50 rpm(770 1 50 rpml*, this means the EVAP system is
purging the canister. To stop the purging temporari-
ly, raise the engine speed above 1,000 rpm with the
accelerator pedal, then slowly release the pedal.*: '99 - 00 models
9. Let the engine idle for one minute with the head-
lights (Low) ON, and check the idle speed.
ldle speed should be:
38 mod6l:
750 f 50 rpm (in Palk or neutrall'99 - 00 modols:
730 t 50 rpm (in Palk or neutral)
10. Turn the headlights off. Let the engine idle for one
minute with the heater fan switch at Hl and air con-
ditioner on, then check the idle speed.
ldls spqed should be:'98 model:
780 t 50 rpm (in Park or neutrall'99 - 00 mod€ls:
7701 50 rpm lin Park or neutral)
lf the idle speed is not within specification. see the
Symptom Chart on page 11-64.
ADJUSTING
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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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Intake Air System
Air Cleaner
Air Cleaner Eloment Rsplacomsnt
NOTE: Do not clean the air cleaner element by blowingit off with compressed air,
AIR CLEANER ELEMENTNo.mal conditions:Replace air cleaner element every30,000 miles {48,000 km) or 24months whichever comes first.Severe condition3:Replace air cleaner element every15,000 miles 124,000 km) or 12months whichever comes tirst.
m
11-194
Throttle Cable
Inrpection/Adiustmcnt
1. Stan the engine. Hold the engine at 3,000 rpm with noload (in Park or neutral) until the radiator fan comeson, then let it idle.
2. Check that the throttle cable operates smoothly withno binding or sticking. Repair as necessary,
3. Check cable free play at the throttle linkage. Cabtedeflection should be 10- 12 mm (3/8 - 1l2in.l.
'97 - 98 modols:
CABLEBRACKET
LOCKNUT
DEFLECTION10-12mmBIA- 112 i^l
'99 - 0O modsls:
lf deflection is not within specs, loosen the locknut,turn the adjusting nut untilthe deflection is as speci-fied, then retighten the locknut.
With the cable properly adjusted. check the throttlevalve to be sure it opens fully when you push theaccelerator pedal to the floor. Also check the throt-tle valve to be sure it returns to the idle position
whenever you release the accelerator pedal.
DEFLECTIONl0-12mft
Bla - 112 inl
NUT
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lnstellation
1. Open the throttle valve fully, then install the throttle
cable in the throttle linkage, and install the cable
housing in the cable bracket.
97 - 98 modols:
THRoTTLE LINKAGE CABLE
INNER CABLE
- (Xl modols:
LOCKNUT
'99
2.Sta.t 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.
Hold the cable sheath, removing all slack from the
cable.
Set the locknut on the cable bracket.
Adiust the adjusting nut so that its free play is 0 mm.
Rimove the cable sheath from the throttle bracket,
reset the adjusting nut and tighten the locknut.
ADJUSTING
BRACKET
'97 - 98 modals:
lhere should beno clearance.
AD.'USTING NUT
'99 - 00 modeb:
CABLEBRACKET
9.8 N.ml'1.0 kgt'm,7.2 tbr.ft)
9.8 N.m(1.0 kg{.m,7.2lbllrl
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Intake Air System
Throttle Body
Doscription
The throttle body is a single-barrel side-draft type. The
lower portion of the throttle valve is heated by engine
coolant from the cylinder head. The idle adjusting screw
which regulates the bypass air is located on the top of
the throttle bodv.
The illustration shows'97 - 98 models,'99 - 00 rnodelsare similar.
1 1-196
lnspection
Check that the throttle cable operates smoothly without
binding or sticking.
lf there are any abnormalities, check for:. Excessive wear or play in the throftle valve shaft.. Sticky or binding throttle lever at the fully closed posi-
tton.
. Clearance between throttle stop screw and throttle
lever at the fully closed position.
97 - 98 models:
THROTTLE LINKAGE
Replace the throttle body if there is excessive play in the
throttle valve shaft or if the shaft is binding or sticking.
THROTTLE LINKAGE
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Removal
'97 - 98 models:MAP SENSOR
R
,:4W)
TP SENSOR
FAST IDLE THERMOVALVE (A/T onlyl
'99 - O0 models:
TP SENSOR
a
F(\g-.-'
22 N.m
12.2 kgl m,16 tbtft)
FAST IDLE THERMOVALVE lA/T only)
NOTE:
. Do not adjust the throttle stop screw.
. After reassembly, adjust the throftle cable (see page 11-194).
. The TP sensor is not removable.(cont'd)
11-197
GASKET
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