Page 197 of 1413
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
Page 201 of 1413
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
Page 203 of 1413
G) FUEL PUI-SATION DAMPER
@ AIR CLEANER(D RESONATOR6 imrlre arR Bypass (tAB) coNTRoL DIAPHRAGM
VALVE(D) IITITP IIN BYPASS {IAB) COTROL SOLENOID VALVE
ds) INTIXT AIR EYPASS TIABI VACUUM TANK
rio'l rnrarg ltn BYPASS (lABl cHEcK vALvE
6 rsnee wav cATALYTtc coNvERTER lrwc)
6 posrnve cRAf{KcAsE vENTILATIoN {Pcv) vALVE
6 evlponlrtve EMtsstot{ tEvAPl coNTBoL cANlsrER
6 evlponltvE EMtssloN {EvAP} PURGE coNTRoL
SOLENOID VALVE6i EVAPORATIV€ EMISSION (EVAPI PURGE CONTROL
DIAPHRAGM VALVE
6o ivlpoalrtve Eutsstof{ IEVAPI rwo wAY vALvE
c) HEATED OXYGEN SENSOR lHO2Sl
€) MANIFOLD ABSOLUTE PRESSURE IMAPI SENSOB
O EI{GINE COOLANT TEMPERATURE {ECT} SENSOR
€) INTAKE AIR TEMPERATURE {IAT) SENSOR
@ KNOCK SENSOR tKSl
@ IDLE alR coNTRoL llAcl vALvE
O FAST IDLE THERMO VALVE
@ FUEL INJECTOR
@ FUEL FILTER
@ FUEL PRESSURE REGULATOR
O) FUEL PUMP (FPI
@) FUEL TANK
@ FUEL TANK EVAPORATIVE EMISSION IEVAPI VALVE
11-11
Page 228 of 1413

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
Page 232 of 1413

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
Page 253 of 1413

PGM-FI System
Intake Air Temperature (lAT) Sensor
----:-- z ---L /-h6l- I t0 l- The Malfunction Indicator Lamp (MlL) indicstes Diagnostic Trouble Cod6 (DTC) 1O: A problem in/ | / - the Intake Air TemDerature (lAT) Sensor circuit,
The IAT Sensor is a temperature dependant resistor (the.mistor). The resistanc€ of the thermistor d6creases 8s the
intake air temDeratura incroases as shown below.
)1611:till/ ---l- z ---i-\
THERMISTOR
RED/YELI + )
RESTSTAXCE tmt
Bl8Bl onglnc:
-a a2 aa roa .t7a 212 a t |l-20 o 20 rto ao I t6 rro t.cl
I TAKE AIR TEiiIPTFATURE
818C1 .nglnc:IAT SEI{SOR
11-62
wi.a sido
- Th! *llL hs b!!n Egortad on.- \|
rdr dra SCS rhon connrcto.conn.ct.d lt . psg. 1l-341.cod. 10 l. hdlclt.d.
Do the ECM Resot kocoduro {se€pago 11-35).
Turn the ignition switch ON.Into.n{tlont failuro. rys-r.m ir OK .t thi. iim.(toat drlvc m6y b6arooa!!1ryt.Ched( tor poor clnncc-lioiE or loote wlrar 6tC223 lloc.tod rightlhock toworl, C12O(lAT renrcrl and ECM.
ls the MIL on and doos itindicate code 10 ?
Turn the ignition swiich OFF.
Oisconnoct tho 2P connector fromthe IAT sensor.
Meosu.e resistonc€ between the2 torminals on the IAT aengor.
ls thero 0.4-4.0 k0?Rlobco tho IAT aonsor.
(To pago 1'l-63)
Page 269 of 1413
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
Page 465 of 1413
S.fdl.enorl! L&l indicdor lighlblinks fourtoon tlmoa.
ls the Malfunction IndicatorLamp (MlL) onl
Stan the ongine and warm it upto normal operating temperature{th€ radiator lan com€s on).
Shift to E position,
Turn rhe ignition switch OFF.
Possible Cause
. Sh"rt ". "e"" i" FAS |YEU ,"rirt. Fsulty ECM.
Connect the Test Harness be-tween the TCM and connociors{see page 14-491.
Turn the ignition switch ON andwsit for at least two seconds.
o oooooo ooo ooo l.tto.oodooo l:,gEoo.ottl o ooooo oooo o
o oooo oooooooo l:OOOO OO 60 l.,OO{tO.O6,'l o oooooooooo
Measure lhe voltage betwgan thso16l+ ) and A25 or A26(- | tor-mrnals.
lcont'd)
Ropair tho PGM-FI Syrtom lloo..ctlon 111.
Chock for looro TCM connoctora.lf noco$ary, subatituta a known-good TCM and .ech€ck.ls thoro approx. 5 V?
Turn the ignition switch OFF.
Dkconnect the Test Harness fromthe TcM.Leave connect€d to car harness.
Turn the ignition switch ON.
fo page 14-74
14-73