Iac valve HONDA INTEGRA 1994 4.G Workshop Manual

Intake Manifold
Replacement
NOTE: Use new O-rings and gaskets when reassembling.
CAUTION: Check for tolds or scratches on the aurface ot the gasket. Roplace with a now gasket it damagod,
81881 engine:
5r0.8mm6 N'm {0.6 kgl.m.4 rbr.ftlINTAKE AIRTEMPERATUREIIATI SENSOR
'*o*ot'u""'""N
5xO.8mm6 .m (0.6 kg{.m.4 tbf.ftl
O-RINGReplace.
IiITAKE MANIFOLDReplace iI cracked orit mating s!rtaces arodamag€o.
PURGE CONTROLSOLENOID VALVE
8 x 1.25 mm22 N.r 12.2 kgl.m,'16 tbt.ftt
IDLE AIR
GASKETSReplace.
I x 1.25 mm20 N.m (2.0 kgt.m.14 rbf.ftl
O.RINGReplace.{IACI VALVEBe careful notto damage.THROTTLE
8 x 1.25 mm
BODY
O-RINGSBeplace.
24 N.m (2.4 kgf'm,17 rbf.ft)
8 x 1.25 mm23 N.m (2.3 kgl.m,17 lbf.frl
BRACKET"o
aYc
g
/
1.25 mmN.m (2.4 kgl'm,rbf'ft1
8x2417
8 x 1.25 mm24 N.m (2.4 kgl'm.17 tbr.ftlTHERMOVALVE8e careful not todamage.
9-2

NOTE: Use new O-rings and gaskets when reassembling.
CAUTION: Chock for folds 01 scratches on th6 surfac6 of tho gaskot. Replace wilh a new gasket if damaged.
818C1 engino:
INTAKE MANIFOLDReplace il cracked oril mating surfaces are
5 x O.8 rnm6 N.m 10.6 kgl.m,4 tbt.ttl
lI
{,/
?,/
EVAP PURGE CONTROLVALVEdamageo.
IAT SENSOR
5xO.8mm6 N.m 10.6 kgf.m,4 tbf.ftl
INTAKE AIRBYPASS VALVE
IAC VALVEBe carelul notlo oamage.
O.RINGSReplace.
GASKETSReplace.
O.BI GReplace.
BODY
INTAKE MANIFOLDCHAMBER
8 x 1.25 mm23 N.rn 12.3 kgt'm,17 tbf.frl
I x 1.25 mm22 N.m 12.2 kgl.ft,t6 tbt.tt)
BRACKET
8 r 1.25 mm24 N.m {2.4 kgf.h,t7 rbr.ftl
8 x t.25 mfi24 N.m (2.4 lgf.m.17 tbt.ft)I r 1.25 lnm24 N.m 12.4 kgt.m,17 tbt.ftl
8 x 1.25 mm20 .m (2.0 kgt.m,14 tbf.ftl
THROTTLEAODY
FAST IDL€ THERMO VALVEBe carelul not to damage.
HEATER BYPASSPIPE
o-Rt GsReplace.
I x 1.25 mm24 N.m (2.4 kgl.m, 17lbf'ft|
9-3

ENGINE COMPARTMENT HOSE CONNECTIONS:
Bl88l engine:FAST IDLETHERMOVALVE
THERMOSTATHOUSIITGIDLE AIR CONTROLIIAC} VALVE
O'RINGReplace.
BREATHER PIPE
O-RINGReplace.
HEATER HOSES
818C1 engine:
ENGINE OILCOOLER
IAC VALVE
HEATER BYPASSPIPE
FAST IDLETHERMOVALVE
THERMOSTATHOUSING
BREATHER PIPE
HEATEB HOSES
10-3

Component Locations
lndex
B18Cl ongino:
THROTTLEPOSITION (TP}
SENSOR
MANIFOLD AESOLUTEPRESSURE (MAPI SENSOR
Troubleshooting, page 1 1-52
EVAPPURGE CONTROLSOLEiIOID VALVETroubleshooting,page 11-137
VALVE
INTAKE AIR TEMPERATURE
IIAT) SENSORpage 11-62
THROTTLE CABLEInspection/Adiustment, page 'l 1-1 19
lnstallation, page 1 1-1 19
IOLE AIF CONTROL (IACI VALVETroubleshooting. page 1 1 -82
Troubleshooting,page 1 1-6O
TOP DEAD CENTER/CRANKSHAFTPOSITION/CYLINDER POSITION
{TDC/CKP/CYPI SEI{SORTroubl€shooting. Page 1 1 -56POWER STEERING PRESSURE (PS'I
swtTcHTroubleshooting, page 1 1-93ELECTRICALLOADDETECTORIELD}Troubleshooting,page.1 1-70
IGNITION CONTNOL MODULE OCMI
Troubleshooting, Psge 1'l-66
ENGIT{E COOLANT TEMPERA
{ECT} SEI{SORTroubleshooting, Pag€ 1 1-58
sElrlsoR tKslTroubfeshooting, page 1 1 -7 4
HEATED OXYGEN SENSOR (HO2S}
Troubleshooting, pages 11-46, 47
FAST IDLEInspection, page 1 'l -94
11-4

AIR CLEAI{ER IACL)Replacoment,11-117
THROTTLE BODY (T8I
Inspsction, page 1 1-120Disassembfy, page 11'122THROTTLE CABLEInsDection/Adjustment, pages 1 l-'l 18, 1 19
Inslallation, pages 1 1-1 18, 119
POSITIVE CRA KCASEvEt{TtLATtOt{ (PcVl VALVEInspection, psgo 1 l-134
INTAKEAIREYPASS IIABIco TnoLSOLENOIDVALVE (B18Cl .ngino onlylTroubl6shooting,page 1 1-124
INTAKEAIRBYPASS (IABI
co TROLOIAPHRAGM{Bl8C1 ongino onlylTroubleshooting,page 11-124
I
RESONATOR
ENGI]TE CONTROL MODULE {ECM)Selt-diagnostic Procedures, page 1 1-34Troubfeshooting, page 1 1 -42
MAIN RELAYRelay Testing, page 1 1- 111Troubleshooting, pag€ 1 1-112SERVICE CHECX CONNECTOR (2PI
56ll.diagnostic Procedures, page'l 1-34
11-5

ENGINECOOLANT
@ FUEL TAI{K EVAPORATIVE EMISSION (EVAP} VALVE
G) FUEL PULSATION DAMPER
@ AIR CLEANER
@) RESONATOR
@ THREE WAY CATALYTIC CONVEnTER (TWC)
o POS|TIVE CRANKCASE VEITITILAT|ON IPCV) VALVE
@ EVAPOBATIVE EMISSION IEVAP) COI{TROL CANISIER
@ EvApoRATrvE EMrssroN IEVAP) PURGE coNTRoL
SOLENOID VALVE
@ EVAPORATTVE EMISSION (EVAP) PURGE CONTROL
DIAPHRAGM VALVE(iD EVAPORATIVE EMISSION (EVAPI TWO WAY VALVE
|l
U]
HEATED OXYGEI{ SEI{SOF (HO2S}
MANIFOI.D ABSOLUTE PRESSURE (MAP) SEI{SONENGINE COOLANT TEMPERATURE IECT} SENSORINTAKE AIR TEMPERATURE IIAT} SEI'ISORIDLE AIR CONTROL IIAC) VALVEFAST IDLE THERMO VALVEFUEL II{JECTORFUEL FILTERFUEL PRESSURE REGULATONFUEL PUMP IFP)FUEL TAI{K
11-9

Troubleshooting
Self-diagnostic Procedures (cont'dl
':818C1 engine
a lf codes other than those listed above are indicated, verifv the code. lf the code indicated is not listed above, replace
rhe ECM.
a The MIL may come on, indicating a system problem when, in fact, there is a poor or intermittent electricalconnection.
First, check the electrical connections, clean or repair connections it necessary.
o The MIL and @ indicator light may light simultaneously when the Diagnostic Trouble Code (DTC) 6, 7 or 17. Check
the PGM-Fl system according to the PGM-Fl system troubleshooting, then recheck the l!! indicator light. ll it lights,
see page 14-5O, 51.
a The MIL does not come on when there is a malfunction in the A/T Fl signal or Electrical Load Detector (ELDI circuits.
However, it will indicate the codes when the Service Check Connector is shorted.
DIAGNOSTIC
TROUBLE
CODE (DTCISYSTEM INDICATEDPsge
oENGINE CONTROL MODULE IECM)11-42
,lHEATED OXYGEN SENSOR IHO25)1 1-46
aMANIFOLD ABSOLUTE PRESSURE {MAP SENSOR)11-52
4CRANKSHAFT POSITION (CKP SENSOR)1 1-56
oENGINE COOLANT TEMPERATURE (ECT SENSOR)11-58
THROTTLE POSITION (TP SENSOR}11-60
ITOP DEAD CENTER POSITION (TDC SENSORI1 1-56
9No. 1 CYLINDER POSITION (CYP SENSOR)1 1-56
10INTAKE AIR TEMPERATURE (IAT SENSOR)11-62
13BAROMETRIC PRESSURE (BARO SENSOR}1|-64
14IDLE AIR CONTROL (IAC VALVE}11-42
tcIGNITION OUTPUT SIGNAL11-66
toFUEL INJECTOR1't-102
17VEHICLE SPEED SENSOR {VSSI11-68
20ELECTRICAT LOAD DETECTOR (ELD)'t 1-70
21VARIABLE VALVE TIMING & VALVE LIFT ELECTRONIC CONTROL SOLENOID
VALVE {VTEC SOLENOID VALVE)'6-36
22VARIABLE VALVE TIMING & VALVE LIFT ELECTRONIC CONTROL PRESSURE
SWITCH (VTEC PRESSURE SWITCHI-6-38
23KNOCK SENSOR {KS}-11-7 4
30A/T FI SIGNAL A11-76
3'rA/T FI SIGNAL B1 1-76
4'lHEATED OXYGEN SENSOR (HO25} HEATER11-47
43FUEL SUPPLY SYSTEM1 1-50
11-36

PGM-FI System
System Description
ENGINE CONTROL MODULE (ECMIOUTPUTS
PGM-Fl System
The PGM-Fl system on this model is a sequential multipon fuel injection system,
Fuol Iniector Timing and Duration
The ECM contains memories tor the basic discharge durations at various engine speeds and manifold pressures. Thebasic discharge duration, after being read out from the memory, is turther modilied by signals sent from vanous sensofsto obtain the final discharge duration.
ldle Air Control
ldle Air Control Valve (lAC Vatve)
When the engine is cold, the A/C compressor is on, the transmission is in gear (A/T only) the brake pedal is depressed,the P/S load is high, or the alternalor is charging, the ECM controls current to the IAC Valve to maintain correct idle soeed.
lgnition Timing Controla The ECM contains mamories for basic ignition timing at various engine speeds and manifold pressures. lgnition timingis also adjusted for engine coolant temperature.a A Knock Control System is also used. when detonation is detected by the knock sensof. the ignition timing is retarded(B18Cl engine).
Other Control Functions
1. Starting Control
When the engine is started. the ECM provides a rich mixture by increasing fuel injector duration.2. Fuel Pump Control
a When the ignition switch is initially turned on, the ECM supplies ground to the PGM-Fl main relay that suppliescurrent to the fuel pump tor two seconds to pressurize the tuel system.a When the engine is running, the ECM supplies gfound to the PGM-Fl main relay that supplies current to the fuel pump.a When the engine is not running and the ignition is on, the ECM cuts ground to the PGM-FI main relav which cutscurrent to the fuel pump.
TDC/CKP/CYP Sensor
MAP Senso.
ECT Sensor
IAT Sensor
TP Sensor
HO2S
vss
BARO Sensor
ELD
Starter Signal
ALT FR Signal
Air Conditioning Signal
A/T Gear Position Signal
Battery Voltage {lcN. 1)
Brake Switch Signal
PSP Switch Signal
Knock Sensor'
VTEC Pressure Switchr
Fuel-lnjectors
PGM-FI Main Relay (Fuel Pump)
MIL
IAC Valve
A/C Compressor Clutch Relay
Radiator Fan Relav
Condenser Fan Relav
ALT
rcM
EVAP Purge Control Solenoid
HO2S Heater
VTEC Solenoid Valve'
IAB Control Solenoid Valve*
lFuet tnjector Timing and Duration]
I Electr..l"ldle Contr;il
Fit'e' contr; Funcrfit
l6tio; Ttntrlg c..trol
tEcM aack-,rp Functiorlsl
': 818C 1 €ngine
11-40

System Description
The idle speed ot lhe engine is controlled by the ldle Air Control {lAC) Valve.
The valve changes the amount ot air bypassing into the intake manifold in response to electric current controlled by the
ECM. When the IAC Valve is activated, the valve opens to maintain the proper idle speed.
#l' ----rTo FGM-FIMAINRELAY
VARIOUSSENSORS
IAC VALVE
FASTIDLETHERMOVALVE
INTAKE MAI{IFOLD
(cont'd)
BLK
r
11-79

ldle Control System
System Description (cont'd)
1 . Atter the engine slarts. the IAC valve opens for a censin time, The amount ot air is increased to raise the idle soeedabout 15O-3OO rom.
2. When the coolant temperature is low, the IAC valve is opened to obtain the proper fast idle speed. The amount ofbypassed air is thus controlled in relation to the engine coolant temperature.
IDI-E SPEEDlrpm)
176
80
ENGINECOOLANT TEMPERATURE
t"Fl(oct
11-80