1998 HONDA INTEGRA radiator

PGM-FI System
System Description
ENGINE CONTROL MODULE (ECM)OUTPUTS
*1: USA*2: 818C1 engine*3: A,/T*4: 818C1, 818C5 engines
PGM-FI Sy3tem
The PGM-Fl system on this model is a sequential multiport fuel injection system.
Fuel lniector Timing and Duration
The ECM contains memories for the basic discharge durations at various engine speeds and manifold pressures. The
basic discharge duration, after being read out from the memory. is further modified by signals sent from various sensors
to obtain the final discharge duration.
ldle Air Control
ldle Ai. Control Valve (lAC Valve)
When the engine is cold, the Ay'C compressor is on. the transmission is in gear (Ay'T only)the brake pedal is depressed, the
P/S load is high, or the alternator is charging, the ECM controls current to the IAC Valve to maintain correct idle speed.
lgnition Timing Control
. The ECM contains memories for basic ignition timing atvarious engine speeds and manifold pressures, lgnitiontiming
is also adjusted for engine coolant temperature.
. AKnockControl System isadoptedwhich sets the ideal ignition timing for the octane n um ber of gasoline used*r,
Other Control Functions
L Starting Control
When the engine is started, the ECM provides a rich mi{ure by increasing fuel injector duration.
2. Fuel PumD Control
. When the ignition switch is initially turned on, the ECM supplies ground to the PGM-FI main relay that supplies
current to the fuel pump for two seconds to pressurize the fuel system.
. When the engine is running, the ECM supplies ground to the PGM-FI main relay that supplies current to the fuel
DUmO.
. When the engine is not running and the ignition is on. the ECM cuts ground to the PGM-FI main relay which cuts
current to the fuel oumo.
INPUTS
TDc/CKP/CYP Sensor
CKF Sensor
MAP Sensor
ECT Sensor
IAT Sensor
TP Sensor
HO2S
VSS
BARO Sensor
ELD*1
Starter Signal
ALT FR Signal
Air Conditioning Signal
A,/T Gear Position Signal*3
Battery Voltage (lGN.1)
Brake Switch Signal
PSP Switch Signal*'
Knock Sensor*1
VTEC Pressure Switch*4
Fuel Tank Prssure Sensor
Fuel InjectorTiming and Duration
Electronic ldle Control
Other Control Functions
lgnition Timing Control
ECM Back-uD Functions
Fuel-lnjectors
PGM-Fl Main Relay (Fuel Pump)
MIL
IAC Valve
A,/C Compressor Clutch Relay
Radiator Fan Belay*1
Condenser Fan Relay
ALT*1
rcM
EVAP Purge Control Solenoid
Valve
H02S Heater
VTEC Solenoid Valve*'
IAB Control Solenoid Valve*,
EVAP Bypass Solenoid Valve
EVAP Control Canister Vent
Shut Valve
11-48

PGM-FI System
Manifold Absolute Pressure (MAPI Sensor (cont'dl
tF'r'sl li:"J:ilfi::il***:ilHi""k:"
code (Drc) P0108' A hish vo*ase (row vacuum) probrem in the
Thc MIL has b6en reoortod on.OTC P0108 is stored.
Problem veritication:1. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator fan comes on, thenlet it idle.2. Check the MAP wlth the scantool,
Intermittent f.ilure, svstem is OKal this time. Check lor Door con-nections or loose wires at C114{MAP sensor} and ECM.
ls 101 kPa (760 mmHg,30.0 in.l-lg),1.0 V or higher indicated?
Chock tor an opcn in th. MAPs€nsoa:1. Turn the ignition switch OFF.2. Disconnect the MAP sensor3P connector.3. Install 6 jumper wire betweenthe MAP sensor 3P connectorterminals No.3 and No.2.4. Turn the ignition switch ON (ll).
5. Ch€ck the MAP with the scantool.
ls 101 kPa (760 mmHg,30.0 in.Hg),1.0 V or higher indicated?
Check tor an open in wire (SG1
linel:1. Remove the jumper wire.2, Measure voltage between theMAP sensor 3P connector teFminals No. I and No.2.
Repair open in the wire betweenECM l012l and MAP s€nsor.ls there approx.5 V?
Check for an open in the wire{MAP line):1. Turn the ignition switch OFF.2. Install a jumper wire on theECM co n nector terminalsbetween D3 and Dl2.3. Turn the ignition switch ON lll).4. Check the MAP with the scantool,
ls 101 kPa (760 mmHg,30.0 in.Hg),1.0 V or higher indicated?Repair open in the wires betweenECM {D3, and MAP s6Gor.
Substitut€ a known-good ECMand recheck. It normal MAP isindicaied, rgplace the originalECM.
MAP SENSOR 3P CONNECTOR {C114}
Wire side of female terminals
L
vccr{YEL/RED)
MAP IWHT
JUMPERWIRE
SG1 (GRN/WHT}
Wire side of female terminals
1 1-56
{GRN/WHT)I ] {RED/GRN)
ECM CONNECTOR D {16P}
L

The scan tool indicates Diagnostic Trouble Code (DTC) P1128: Manifold Absolute Pressure (MAP) lower rhan
expected.
The scan tool indicates Diagnostic Trouble Code (DTC) P1129: Manifold Absolute Pressure (MAP) higher than
expected.
- Th€ MIL has b€en reoortod on.- DTC Pl128 is stored.
Problem vorification:1. Turn the ignition switch ON {ll}.2. Check the MAP with the scantool,
ls 54.1 kPa (406 mmHg, 16.0in.Hg) or higher indicated?Intermittent laihre, system i3 OKat this time.
- The MIL has been reooned on.- DTC P1129 is stored.
Problem verification:1. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator fan comes on, thenlet it idle.2. Check the MAP with the scantool.
ls 43.3 kPa (325 mmHg, 12.8in.Hg) or less indicated?Intermittoni lailure.3ystem is OKat this time.
11-57

PGM-FI System
Engine Coolant Temperature (ECTI Sensor
Ip01161 Ihe,scaltool indicates Diagnostic Trouble Code (DTC) P0116: A range/performance problem in the Engine: Coolant Temperature {ECT) Sensor circuit.
The ECT Sensor is a temperature dependant resistor (thermistor). The resistance of the thermistor decreases as the engine
coolant temperature increases as shown below.
RESISTANCEtkol
! 32 68 104 140 i 76 212 248 { "F)-20 o 20 'ra, qt Il rd' t20 r'c)
ENGINE COOLANT TEMP€RATURE
P01 16, troubleshoot those DTCS first, then trou-NOTE: lf DTC P0117 andlo( Po'l'18 are stored at the same time as DTC
bleshoot DTC P0'l16.
Possible Cause
. ECT sensor deterioration
. Malfunction in the thermostat and the cooling system
lroubleshooting Flowchart
I
1 1-60
THERMISTOR
- Th€ MIL has been reoorted on.- DTC P0116 is stored.
Problem veritication:1. Start lhe engine. Hold theengine at 3,000 rpm with noload (in Park or neutrall untilthe radiatorlan comes on, thenlet it idle.2. With the scan tool, check theECT,
Inlermittent failure, system is OKat this time. Chock tho thermostaland th€ cooling syst6m.
ls 176 - 200"F (80 - 93'C) or0.4-0.TVindicated?
Check the thermostat and thecooling system. It th€y ara OK,reolace the ECT sensor,

The scan tool indicates Diagnostic Trouble Code (DTC) P0122: A low voltage problem in the Throttle Position{TP) sensor circuil.
The TP Sensor is a potentiometer. lt is connected to the throttle valve shaft. As the throttle position changes, the throttleposition sensor varies the voltage signalto the ECM.
ARUSHHOI.DER
BRUSH 5
FULLTHROTTLE
TP SENSOR CONNECTOR IC115)
Wire side of temale terminals
ECM CONNECTOR D {16P)
(GRN/BLUI
Wire side ot female terminals
sG2 / -\
fr rrr r 'tr\
- 1 2 3)
|{- f- /
| _-,/tlI /6 I TPS-\j/
Terminalside of maletermrnats(To page 11-64)
The MIL has be€n reDort€d on.DTC P0122 is stor€d.
Problem veritication:1. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator fan comes on, thenturn the ignition switch OFF.2. Turn the ignition switch ON (ll).
3. Check the throttle positionwith the scan tool.
ls there approx. 10% whenthe throttle is fully closedand approx.90o/o when thethrottle is fully opened?
lntermittenl tailure, system is OKat this time. Check tor poor con-nections or loose wires at Cl15{TP s€nsor) end ECM.
Check lor an open in ihe wire(VCC2line):
1. Turn the ignition switch OFF.2. Disconnect the TP sensor con,nector,3. Turn the ignition switch ON (ll).4. Measure voltage betweenTP sensor connector terminalsNo. l and No. 3.
ls there approx. 5 V7
Check fo. an open in wire IVCC2line):lleasure voltage between ECMconnector terminals D10 and D11.
R.p.ir opon in tho wire betwoenECM {D101 and TP sen3or.ls there approx. 5 V?
Substitute a known-good ECMand recheck. lf pr6sc.ibed volt-age ia now available, replaco theoriginalECM.
Check for an open or 3hort in TP3ensor:1. Turn the ignition switch OFF.2. Measure resistance betweenTP sensor terminals No. '1 andNo.2 with the throttle fullyctoseo,
OUTPUT VOLTAGE {V)
4
RESISTOR3
2
TERMINAL
I
o
THROTTLEOPEI{INGBUS}IINGIDLE
sG2{GRN/BLK)vcc2IYEL/BLU}
vcc2{YEL/BI
l\e
4E
i2iRN,
. llLI5
6/101t 12
t515
(cont'd)

The scan tool indicates Diagnostic Trouble Code (DTC) P0123r A high voltage problem in the Throttle position(TP) sensor circuit,
TP SENSOR CONNECTOR {Cl15I
sG2{GRN/BLK}(YEL/BLU)
Wire side of female terminals
Th€ MIL has been reported on.DTC P0123 is stored.
Problem veriticationl1. Start the engine. Hold theengine at 3,000 rpm whh noload (in Park or neutral) untilthe radiator tan comes on, thenturn the ignition swhch OFF.2. Turn the ignition switch ON (ll).3. Check the throttle positionwith the scan tool.
ls there approx. l0% whenthe throttle is fullyclosedand approx. 90% when thethrottle is fully opened?
Intermittoni {ailure, system is OKal this time. Check tor poor con-nections or loose wires at C115{TP sensor} and ECM.
Check for an open in the TP sen-sot:1. Turn the ignition switch OFF.2. Disconnect the TP sensor con,nectot.3. Turn the ignition switch ON (ll).4. Measure voltage between TPsensor connector terminalsNo.3 and No.'1.
ls there approx. 5 V?
Check for an open in th€ wire(SG2linel:
Measure voltage between ECMconnector terminals Dl0 and 011.
Ropair open in the wir6 betweenECM lD11l and TP sensor.ls there approx. 5 V)
Substitute a known-9ood ECMand rocheck. lf prescribed volt-age is now availablo, roplace theoriginal ECM.
ECM CONNECTOR D I16PI
Wire side of female terminals
(cont'di
1 1-65

Primary Heated Oxygen Sensor (HO2S) lsensor 1l
The Heated Oxygen Sensor {HO2S) detects the oxygen content in the exhaust gas and signals the ECM. In operation, theECM receives the signals from the sensor and varies the duration during which fuel is iniected. To stabilize the sensor,soutput, the sensor has an internal heater and the sensor element is coated with a catalyst. The HO2S is installed in TWChousing (818C'1, 818C5 engines) or exhaust pipe B {81881 engine).
ztFcoNtAEI."EMEI'IT
SENSORTERMINALVOLTAGE IV)
HEATERIIEATERTERMINAL
RICH. AIR. * LEANFUELRANO
Thescantool indicates Diagnostic Trouble Code IDTCI PO13l: A low voltage problem in the primary
Heated Oxygen Sensor (HO2S) (Sensor 1) circuit.
- Th6 MIL h.r baan.ago.t.d on.- DTC m131 it 3to..d.
Problcm vcrificrtion:1. Do the ECM Reset Procedure.2. Start the engino. Hold theengane at 3,000 rpm with noload lin Park or neutral) untilth€ radiator Ian cofies on.3. Test-drive with the A,/T in Eposition, M/T in 4th gear.4. Check the Primary flO2S {S€n-sor 1) output voltage with thescan tool during accelerationusing wide open throttle.
Intarmittcnt f.ilur., 3yatam b OK.t thia tima. Ch.ck for poor con.nrctiona or loosa wiraa at C113(Prim.ry HO2S ls.n.or lll rndECM.
Chock the fuel pres6ure (see psge11-'t 18).
{To page 11-68)
(cont'd)
11-67

JThe scan tool indicates Diagnostic Trouble Code (DTC) P0132: A high voltage probtem in the primary HeatedOxygen Sensor (HO2S) (Sensor 1) circuit.
Problem veritication:1. Do th; ECM Reset procedure.
2. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator fan comes on,3. Test-drive with the A/T in Elposition, M/T in 4th gear.4. Check the Primary l-lO2S (Sen-sor 1) outprrt voltage with thescan tool during decelerationusrng comptetely closed throt-tle.
YES
Check tor an open in the HO2S:1. Turn the ignition switch OFF.2. Disconnectthe Primary HO2S(Sensorl)connector.
lnstall a jumper wire on the harness side ofthe Primary HO2S(Sensor 1) connector betweenterminals No.1 and No.2.Turn the ignition switch ON t).Check the Prjmary HO2S (Sen-sor'l) output voltage with thescan tool.
Intermittent failur€, svstem is OKat this time. Check for poor con-nectaons or loose wires at C113(Primary HO2S lsensor lll andECM.
5.
PRIMAnY HO2S {Sensor 1) CONNECTOR tC1t3l
PHO2S(WHT}
Wire side of female terminals
ECM CONNECTOR D (16PI
JUMPERWIREPHO2S(WHT)F;r=12 3 !l
sG2
5
./ 1012
13
(GBN/BLU)
Wire side of female terminals
(cont'd )
- The MIL has b€€n ieDorted on.- DTC P0132 isstored.
Replace the Primary HO2S (Sen-sor 11.ls there 1,0 V or more?
Check for an open in the wiros{PHO2S lin6):1. Turn the ignition switch OFF.2. Connect ECM connector termi-nals D7 and Dl1 with a jumper
3. Turn the ignition switch ON 0).4. Checkthe Primary HO2S (Sen-sor 1) output voltage with thescantool.
Repair open in the wire betweenECM (D7) end Primarv HO2S lsen-sor l).
ls there 1,0 V or more?
Substitute a known-good ECMand recheck. lf symptom/indica-tion goesaway. r€place th€ origi-nalECM.
1 1-69