Gas HONDA CIVIC 1996 6.G Repair Manual

Gomponent Locations
L
lndex
D16Y5 engine:
{IATISENSORTroubleshooting,
ELECTRICAL LOADDETECTOR IELD) (USA mod6l)Troubleshooting, page 11 179
THROTTLE POSITION ITP)SENSORTroubleshooting, page 1 1-132
MANIFOLD ABSOLUTEPRESSURE IMAPI SENSORTroubleshooting, page 1'l-115
EXHAUST GAS RECIRCULATION
IEGRI VALVE and EXHAUST GAS
RECIRCULATION IEGRI VALVE
LIFT SENSORTroubleshooting, page'l 1-254
INTAKE AIR TEMPERATUR€
IDLE AIR CONTROL (IAC) VALVE
{M/T)Troubleshooting, page 1 1-194
EXHAUST GAS RECIRCULATION{EGRI CONTROL SOLENOIDVALVE ICW)Troubleshooting. page 1 1-254
EVAPORATIVE EMISSIONIEVAPI PUNGE CONTROLSOLENOID VALVETroubf eshooting, Page 1 1'21 1, 243
CRANKSHAFTPOS|TTON/TOP DEAD CENTER/CYLINDERPOS|T|ON
POWER STEERING PRESSURE(PSP) SWITCH (USAI
Troubleshooting, Page 1 1-212
KNoCK SENSoR (Ks)
(cwl
Troubleshooting, Page 1 1'170ICKP/TDC/CYP} SENSOR(Built into the distributor)Troubleshooting, Page 1 1'172
VEHICLE SPEED SENSORTroubleshooting, Page 1 1-176
FLUCTUATION (CKF} SENSOR
Troubleshooting, Page 1 1 -183
ENGINE COOLANTTEMPERATUREIECT) SENSORTroubleshooting, Page 11 128
IDT.ECONTROL IIACI VALVE
{cw)Troubleshooting, Page 11 198
WAY CATALYTICCONVERTER ITWCITroubleshooting, Page 1 1-252PRIMARY TIEATEDSENSOR {PNIMARY HO2SI
tsENsoR 1t {M/TlTroubleshooting, Page'l 1-146
PRIMARY HEATED OXYGENSENSOR (PRIMARY HO2SI
tsENsoR 1l {cw}Troubleshooting, Page 1 1-139
SECONDARY HEATED OXYGENSENSOR {SECONDARY HO2S){SENSOR 2)Troubleshooting, page 11 153
(cont'd)
1 1-3

System Description
Vacuum Connections
D16Y5 engin6 ('96 - 97 modelsl:
To EVAPORATIVE EMISSION(EVAPI
TWO WAY VALVE
MANIFOLDABSOLUTEPRESSURE IMAPISENSOR
€VAPORATIVEEMISSION IEVAPIPURGE CONTROL SOLENOIDVALVE
EXHAUST GAS BECIRCULATION(EGR) VALVE end EXHAUST GASRECIRCULATION IEGR) VALVELIFT SENSOR
Qo
FRONT OF VEHICLE
To CRUISECONTROLDIAPHRAGM(wath cruise control)
Qo
O: Vacuum hose No.
11-12
EXHAUST GAS RECIRCULATION(EGR) CONTROL SOLENOID VALVE {CVT}\.'.-' \
I
I
)
FUEL PRESSURE REGULATOR

D16Y5 engine l'98 - 00 models):
To EVAPORATIVE EMISSIONtEVAPI THREE WAY VALVE {98 model)
To EVAPORATIVE EMISSIONIEVAP' CONTBOLCANISTERFILTER 1'99 - 00 modelsl
EVAPORATIVE EMISSION {EVAPICONTROL CANISTERVENT SHUT VALVE
To EVAPORATIVE EMISSION
l'99 - 00 modelsl {EVAP)TWO WAY VALVE
EXHAUST GAS RECIRCULATION(EGRI VALVE and EXHAUST GASRECIRCULATION IEGRI VALVELIFT SENSORtcwl
..,.-----.-(CWontylEXHAUST GAS RECIRCULATION
IEGR} CONTROL SOLENOIOVALVE ICVTI
,t'ffi,
ig
EVAPORATIVEEMISSION {EVAP)PURGE CONTROLCANISTER
MANIFOLDABSOLUTEPRESSURE {MAPISENSOR
EVAPORATIVEEMISSION {EVAP)Qo
To CRUISECONTROLDIAPHRAGM(with cruise control)PURGE CONTROL SOLENOIDVALVEFRONT OF VEHICLE
FUEL PRESSURE REGULATOR
o: Vacuum hose No.
(cont'd)
1 1-13
L

Dl6Y5 engine ('96 - 97 modelsl:
o
,6i
@
o@€)@o
@(il(i'
PRIMARY HEATED OXYGEN SENSOR {PRIMARY HO2S,
SENSOR 1'SECONDARY HEATED OXYGEN SENSOR (SECONDARY
HO2S. SENSOR 2l
MANIFOLD ABSOLUTE PRESSURE {MAP) SENSOR
ENGINE COOLANT TEMPERATURE (ECTI SENSOR
INTAKE AIR TEMPERATURE IIAT) SENSOR
KNOCK SENSOR (KS)
CRANKSHAFT SPEED FLUCTUATTON (CKF} SENSOR
IOLE AIR CONTROL (IAC} VALVE
THROTTLE BODY (TBI
FUEL INJECTORFUEL PULSATION DAMPER
FUEL FILTERFUEL PRESSURE REGULATORFUEL PUMP IFPIFUEL TANK
:li Vacuum hose No*: CVT only
FUEL TANK EVAPORATIVE EMISSTON {EVAP) VALVE
AIR CLEANERRESONATORPOSITIVE CRANKCASE VENTIL/ATION IPCVI VALVE
EXHAUST GAS RECIRCULATION IEGR) CONTROL
SOLENOID VALVEEXHAUST GAS RECIRCULATION (EGRI VALVE
EXHAUST GAS RECTRCULATION IEGRI VALVE LIFT
SENSOREVAPORATIVE EMISSION IEVAPI PURGE CONTROL
SOLENOID VALVEEVAPORATIVE EMISSION {EVAP} CONTROL CANISTER
EVAPORATIVE EMISSION {EVAP} TWO WAY VALVE
THREE WAY CATALYTIC CONVERTER (TWCI
{Do(D
@@
@@
@
@@@
(cont'd)
1 1-19
!'a

System Description
Vacuum Connections (cont'd)
D16Y5 engine ('98 modet):
-: Vacuum hose No,*: CW only
(9 POSITIVE CRANKCASE VENTILATION {PCV} VALVE?!J EXHAUST GAS BECIRCULATION (EGR}CONTROLSOLENOIO VALVE'1 ExHAUST GAs RECIRCULATIoN IEGRI VALVE22 EXHAUST GAS RECIRCULATION {EGR} VALVE LIFISENSOR€J EvApoRATtvE EMtsstoN {EvAp} puRGE coNTRoLSOLENOID VALVEq4 PURGE JOINT@ EVAPoRATIVE EMIssIoN {EVAP) coNTRoL CANISTER@ EVAPORATIVE EMISSION IEVAP} BYPASS SOLENOIDVALVE?? EVAPORATIVE EMISSION {EVAP) THREE WAY VALVEITII EVAPORATIVE EMISSION IEVAP} CONTROL CANISTERVENT SHUT VALVEO FUEL TANK PRESSURE sENsoRQlI EVAPORATIVE EMISSION {EVAP}TWO WAY VALVE8' THREE WAY CATALYTIC CONVERTER {TWCI
il) PRIMAFY HEATED OXYGEN SENSOR IPRIMARY HO2S.SENSOR 1)O SECoNDARY HEATEo oxYGEN sENsoR {sEcoNDARYHO2S. SENSOB 2)iq] MANIFOLD ABSOLUTE PRESSURE (MAPI SENSORO ENGINE COOLANT TEMPERATURE IECT) SENSOR5 INTAKE AIR TEMPERATURE {IATI SENSOR! KNOCK SENSOR tKSlO CRANKSHAFT SPEED FLUCTUATIoN {cKF) sENsoFO IDLE AIR coNTRoL {IAc) vALvE99 THROTTLE BODY ITBI@ FUEL INJECToRO FUEL PULSATION DAMPER@ FUEL F -TER@ FUEL PRESSURE REGULAToR[4 FUEL PUMP IFPI(9 FUEL TANK(D FUEL TANK EVAPoRATIVE EMIssIoN IEVAPI VALVEO' AIR CLEANER(D RESoNAToR
11-20

D16Y5 engine ('99 - 00 modelsl:
O) PRIMARY HEATED OXYGEN SENSOR (PBIMARY HO2S,
SENSOR 1)
O SECONDARY HEATEO OXYGEN SENSOR {SECONDARY
HO2S. SENSOR 2)
6] MANIFOLD ABSOLUTE PRESSURE IMAPI SENSOR
rO CruCIruC COOUruT TEMPERATURE IECTI SENSOR
o rrurlxe ln ETUpERATURE 0AT) SENSOR
.d KNOCK SENSOR (KS}
O CN,NruXSXITT SP:ED FLUCTUATION (CKFI SENSOR
@ rou an corurnoL 0Ac) valvE
O THROTTLE BODY (TB)
@ FUEL INJECTOR
E) FUEL PULSATION OAMPER
t? FUEL FILTER
G) FUEL PRESSURE REGULATOR
OI FUEL PUMP (FP)
Gi FUEL TANK
G) AIR CLEANERfi? RESONATOR
Gl posmvr cnglrcAsE VENTILATION (PCV) VALVE
@ EXHAUST GAS RECIRCULATION IEGR} CONTROL
SOLENOID VALVE6 EXHAUST GAS RECTRCULATION (EGR) VAI-VE
rf exxlust cls nectRcuLATloN IEGR) vALvE LIFT
SENSOR@ EVAPORATIVE EMISSION (EVAPI PURGE CONTNOL
SOLENOID VALVE
O} PURGE JOINTio :vaponanve eutssloN (EVAP) coNTRoL cANlsrER
d rvlponlrtve EmtsstoN tEvAPl BYPASS soL-eNolD
VALVE
6 EVAPORATIVE EMISSION {EVAP) CONIROL CANISTER
FILTER
@ EVAPORATIVE EMISSION (EVAPI CONTROL CANISTER
VENT SHUT VALVEOA FUEL TANK PRESSURE SENSOR
6 :vlponlnvg er,/tlssloN tEvAPl TWO WAY VALVE
6 oNgoano nerueltNc vAPoR REcovERY {onvRl VENT
SHUT VALVE
€!) ONBOARD REFUELING VAPOR RECOVERY (ORVRI VAPOR
RECIBCULATION VALVE
@ THREE WAY CATALYTIC CONVERTER (TWCI
(cont'd)
11-21
L

Troubleshooting
Troubleshooting Procedures (cont,dl
ECM/PCM Data
By connecting the OBD ll scan tool or the Honda pGM Tester to the l6p data link connector (DLC), various data can beretrieved from the EcM/PcM. The items Iisted in the table below conform to the sAE recommended practice.The Honda PGM Tester also reads data beyond that recommended bv SAE.understanding this data wil help to find the causes of intermittent fairures or engine probrems,
NOTE:
' The "operating values" given below are approximate values and may be different depending on the environment andthe individual vehicle.. Unless noted otherwise, "at idle speed,, means idling with the engine completely warmed up, Ay'T in position @ or E],M/T in neutral, and the Ay'C and all accessories turned off.
(
DataDescriptionOperating ValueFreeze Data
Diagnostic
Trouble Code(DTC)
lf the ECM /PCM detects a problem, it will store it as acode consisting of one letter and four numbers.Depending on the problem, an SAE-defined code (poxxx)or a Honda-defined code (Plxxx) will be outDut to therester.
lf no problem is detected,
there is no output.
YES
Engine SpeedThe ECM/PCM computes engine speed from the signalssent from the Crankshaft Position sensor.This data is used for determining the time and amount offuel injection,
Nearly the same as
tachometer indication.YES
Vehicle SpeedThe ECM/PCM converts pulse signals from the VehicleSpeed Sensor (VSS) into speed data.Nearly the same as
speedometer indicationYES
Manifold
Absolute
Pressure {MAP)
The absolute pressure caused in the intake manifold bvengine load and speed.With engine stopped:
Nearly the same as atmo-
spheflc pressure
At idle speed:
24 - 31 kPa (180 - 280
mmHg, 7.1 - 11.0 inHg)
YES
Engine Coolant
Temperature
(ECT)
The ECT sensor converts coolant temperature into volt_age and signals the ECM/PCM. The sensor is a thermistorwhose internal resistance changes with coolant temDera_ture. The ECM/PCM uses the voltage signals from theECT sensor to determine the amount of iniected fuel.
With cold engine:
Same as ambient temper,
ature and IAT
With engine warmed up:
176 - 194.F (80 - 90.C)
YES
Heated Oxygen
Sensor {HO2S)(Primary,
Sensor 1)(Secondary
Sensor 2)
The Heated Oxygen Sensor detects the oxygen contentin the exhaust gas and sends voltage signals to theECI\4/PCM. Based on these signats, the ECM/pCM con_trols the airlfuel ratio. When the oxygen content is high(that is, when the ratio is leaner than the stoichiometricratio), the voltage signal is lower.When the oxygen content is low (that is, when the ratiois richer than the stoichiometric ratio), the voltage signalis higher.
0.0 - 1.25 V
At idle speed:
about 0.1 - 0.9 V
NO(Sensor 1)
1 1-86

Troubleshooting
DTClMlL indicationlDatection hsmProbablo CausePage
P0137(63)Secondary Heated Oxygen SensorCircuit Low Voltage(Sensor 2)
Short in Secondary HO2S lSensor 2) circuitSecondary H02S {Sensor 2)ECM/PCI\41 1-153
P0r38 {63)Secondary Heated Oxygen SensorCircuit High Voltage(Sensor 2)
Open in Secondary HO2S (Sensor 2) circuitSecondary HO2S (Sensor 2)EC[I/PCM11-154
P0'139 (63)Secondary Heated Orygen SensorSlow Response(Sensor 2)
Secondary H02S lSensor 2)1l-156
P0141 (65)
Secondary Heated Oxygen SensorHeaterCircuit Malfunction(Sensor 2)
. Open or short in Secondary HO2S (Sensor2) heater circuit. ECM/PCM11-157
P0171 (45)
System Too LeanFuel supply systemPrimary HO2S (Sensor 1)MAP sensorContaminated fuelValve clearanceExhaust leakage
11,164
P0172 (45)
System Too RichFuel supply systemPrimary HO2S (sensor l)MAP sensorContaminated fuelValve clearance
11-164
P0300*16' }l?
andsome ofPo3o1 /r'' \P0302 l72lP0303 l73lP0304 \7 4l
Random Misfirelgnition systemFuel supply systemMAP sensorEGR systemIAC valveContaminated fuelLack of fuel
r1-r66
P0301P0302P0303P0304
/rt\172ll73l\7 4l
- Cylinder 1- Cylinder 2- Cylinder 3- Cylinder 4Misfire Detected
Fuel InjectorFuel Injector circuitlgnition systemLow compressionValve clearance
11 167
P0325*3 (23)Knock Sensor (KS) CircuitMalfunctionOpen or short in Knock Sensor (KS) circuitKnock Sensor {KS)ECM/FCtvl11-170
P0335(4)Crankshaft PositionSensor CircuitMalfunction
Crankshaft Position SensorCrankshaft Position Sensor circuitECM/PCM11-172
P0336(4)Crankshaft PositionSensorRange/Performance
. Crankshaft Position Sensor. Timing belt skipped teeth11-172
P040'r*r (80)Exhaust GasRecirculationInsufficient Flow Detected
' EGR valve. EGR line
P0420(67)Catalyst SystemEfficiency BelowThreshold
. Th.ee Way Catalytic converter. Secondary HO2S11 253
Diagnostic Trouble Code (DTCI Chat (cont'dl
*3: D16Y5 engine (CVT), D16Y8 engine and B1642 engine*4: D'16Y5 engine*16: '98 model+17: '99 - 00 models
,Jla
1 1-98

PGM-FI System
System Description
CKP/TDC/CYP Sensor
MAP Sensor
IAT SensorTP SensorEGR Valve Lift Sensor*'Primary H02SSecondary HO2SVSSBARO SensorELD*'KS€Starter SignalALT FR SignalAir Conditioning SignalA/T Gear Position SignalBattery Voltage {lGN.1}Erake Switch SignalPSP Switch SignalFuel Tank Pressure Sensor*iVTEC Pressure Switch*5Clutch Switch Signal*6Countershaft Speed SensornBMainshaft Speed Sensorrs
-\
----t /
F;ilrr j"-----fi-tri-'r.;l
Fb"t."'i" d" c;;il
F,h"'c;;tr*".io";-l
@."r.l"sc;;ll
EaM/PcM B""k-p F"""till
r\
-:/
Fuel IniectorsPGM-Fl Main Belay {Fuel Pump)MILIAC Valve!y'C Compressor Clutch RelayRadiator Fan Relay*,Condenser Fan RelayALT*'lcMEVAP Purge Control Solenoid
Primary HO2S HeaterSecondary H02S HeaterEGR Control Solenoid Valve*rEGR valve*6EVAP Bypass Solenoid Valve*'EVAP Control Canister Vent Shut
VTEC Solenoid Valve*5DLCLock-up Control Solenoid Valve*aShift Control Solenoid Valve*3Linear Solenoid Valve*3
*1: Dl6Y5 engine*2: USA model*3: CW (D16Y5 ensine), D16Y8 engine and 81642 ensine*4: '96 D16Y8 engine lcoupe),'97 Dl6Y7 engine (coupe: KL model, sedan: KL (LX) model),'97 D16Y8 engine {coupe: all models, sedan: KLmodel),'98-all models,'99'all models,'00-all models+5: D16Y5, D16Y8,816A2 engine*6: M/T (D16Y5 enginei*7: CVT 1D'l6Y5 engine)+8: A/T (D16Y7, D16Y8 engine)*9: '96 D16Y5 engine,'96 D16Y7 engine,'96 Dl6Y8 engine (sedan),'97 D16Y5 engine,'97 Dl6Y7 engine (coupe: KA, KC models, sedan:KA, KC, KL (LX) models, hatchback: all models),'97 D16Y8 engine (sedan: KA, KC modelsi
PGM-FI Sy3lem
The PGM-Fl system on this model is a sequential multipon fuel injection system.
Fuel iniector Timing and Duration
The ECM/PCM contains memories for the basic discharge durations at various engine speeds and manifold air flow rates.
The basic discharge duration, after being read out from the memory. is further modified by signals sent from various sen-
sors to obtain the final discharge duration.
ldle Air Control
ldle Air Control Valve llAC Valve)
When the engine is cold. the A,/C compressor is on, the transmission is in gear, the brake pedal is depressed, the P/S load
is high, or the alternator is charging, the ECM/PCM controls current to the IAC Valve to maintain the correct idle speed.
lgnition Timing Control
. The ECM/PCM contains memories for basic ignition timing at various engine speeds and manifold air flow rates.
lgnition timing is also adjusted for engine coolant temperature.
. Aknockcontrol system was adopted which sets the ideal ignition timing for the octane rating ofthegasoline used.*3
Othgr Control Funqtions
1. Starting Control
When the engine is started, the ECM/PCM provides a rich mixture by increasing fuel injector duration.
2. Fuel Pump Control
. When the ignition switch is initially turned on, the ECM/PCM supplies ground to the PGM-Fl main relay that sup-plies current to the fuel pump for two seconds to pressurize the fuel system.. When the engine is running, the ECI\4PCM supplies ground to the PGM-FI majn relay that supplies current to the fuel
oumo.
. When the engine is not running and the ignition is on, the ECM/PCM cuts ground to the PGM-FI main relay which
cuts current to the fuel pump.
11-104
INPUTS
ENGINE CONTROL MODULE (ECMY
POWERTRAIN CONTROL MODULE (PCM) OUTPUTS

3.
5.
6.
1.
Fuel Cut-off Control
. During deceleration with the throttle valve closed, current to the fuel injectors is cut off to improve fuel economy at
speeds over the following rpm:. D16Y5 engine (M/T):850 rpm. D]6Y5 engine (CVT), D'16Y8 engine (USA M/T): 920 rpm
. Dl6Y8 engine (USA A,/I), D16Y7 engine (USA A,/T);910 rpm
. D16Y8 engine (Canada M/T), D16Y7 engine (canada): 990 rpm
' D16Y8 engine (Canada M/T): 1,000 rpm
. 816A2 engine: 970 rpm
. Fuel cut-off action also takes place when engine speed exceeds 6,900 rpm (D16Y5, D16Y7 engine; D'16Y8 engine:
7,000 rpm. 816A2 engine: 8.100 rpm), regardless of the position of the throttle valve, to protect the engine from
over-rewing. With '99 Dl6Y7 engine (A,/T) and '99 D16Y8 engine (A./T), the PCM cuts the fuel at engine speeds over
5,000 rpm when the vehicle is not moving.
IVC Compressor Clutch Relay
When the ECM/PCM receives a demand for cooling from the air conditioning system, it delays the compressor from
being energized, and enriches the mixture to assure smooth transition to the A,/C mode
Evaporative Emission (EVAP) Purge Control Solenoid Valve*'
When the engine coolant temperature is above 154'F (68'C). the ECM/PCM controls the EVAP purge control solenoid
valve which controls vacuum to the EVAP purge control canister.
Evaporative Emission (EVAP) Purge Control Solenoid Valve*a
When the engine coolant temperature above 154"F (68"C), intake air temperature above 32"F (0'C) and vehicle speed
above 0 mile (0 km/h) or [Ay'C compressor clutch on and intake air temperature above 160"F (41'C)], the ECM/PCM
controls the EVAP purge control solenoid valve which controls vacuum to the EVAP purge control canister.
Exhaust Gas Recirculation (EGR) Control Solenoid Valve*?
When EGR is required for control of oxides of nitrogen (NOx) emissions. the ECM controls the EGR control solenoid
valve which supplies regulated vacuum to the EGR valve
Alternator Control
The system controls the voltage generated at the alternator in accordance with the electrical load and driving mode,
which reduces the engine load to improve the fuel economy.
ECM/PCM Fail-safe/Back-up Functions
1. Fail safe Function
When an abnormality occurs in a signal from a sensor, the ECM/PCM ignores that signal and assumes a pre-pro-
grammed value for that sensor that allows the engine to continue to run.
2. Back-uD Function
When an abnormality occurs in the ECM/PCM itself, the fuel injectors are controlled by a back-up circuit independent
of the system in order to permit minimal driving.
3. Self diagnosis Function lMalfunction Indicator Lamp (MlL)l
When an abnormality occurs in a signal from a sensor, the ECM/PCM supplies ground for the lvllL and stores the DTC
in erasable memory. When the ignition is initially turned on, the ECM/PCM supplies ground for the MIL for two sec-
onds to check the MIL bulb condition.
4. Two Trip Detection Method
To prevent false indications, the Two Trip Detection Method is used for the HO2S, fuel metering-related. idle control
system, ECT sensor, EGR system and EVAP control system self-diagnostic functions. When an abnormality occurs,
the ECM/PCM stores it in its memory. When the same abnormality recurs after the ignition switch is turned OFF and
ON 0l) again, the ECM/PCM informs the driver by lighting the MlL. However, to ease troubleshooting, this function is
cancelled when you jump the service check connector. The MIL will then blink immediately when an abnormality
occurs,
5. Two (or Three) Driving Cycle Detection Method
A "Driving Cycle" consists ot starting the engine. beginning closed loop operation, and stopping the engine. lf misfir-
ing that increases emissions is detected during two consecutive driving cycles, or TWC deterioration is detected dur-
ing three consecutive driving cycles, the ECM/PCM turns the MIL on. However, to ease troubleshooting, this function
is cancelled when you jump the service check connector. The MIL will then blink immediately when an abnormality
occurs.
(cont'd)
1 1-1 05
.1.