PGM-FI System
I
a
a
Ch6ck the PO2SHTC circuit:1. Start engine and keep enginerpm at idle.2. At the engine wire harness,measure voltage betweenPrimary HO2S (Sensor 1) 8Pconnector terminal No. 1 terminal and body ground.
Check for an open in the wire(PG linellMeasurc voltage between PrimaryHO2S (Sensor 1) 8P connector ter-minals No. l and No.2.
ls there morethan 5 V?
Repair opon in the wi.o bEtwoonthe HO2S.nd G101 (located atth.rmonat housingl.
ls there more than 5 V?
Substitule a known-good ECM.nd .echeck. lt 3ymptom/indica-tion 906! rwry, roplace the origi-nal ECM,Check lor a short in the wire
{PO2SHTC line):1. Turn the ignition switch OFF.2. Disconnect ECM connector A(32P)trom the ECM.3. Check for continuity betweenECM connector terminal 46and body ground.
Ropair 3hort in tho wire betwoenthe ECM {46} and the Prim.ryHO2S lson3or 11.
Check for an open in the wire(PO2SHTC linel:Check for continuity betweenECM connector terminal 46 andthe Primary HO2S (Sensor 1)8Pconnector terminal No. 1.
Repair opsn in the wir6 botweenECM {A6} .nd the Primary HO2Slsonror 1).
Substituto a known-9ood ECMand rech6ck. lf symptom/indica-tion goes away, replace the origi-nal ECM.
Heated Oxygen Sensor (HO2S) Heater (Dl6Y5 engine with M/Tl (cont'd)
(From page 11-161)PRIMARY HO2S (SENSOR 1} 8P CONNECTOR {Cl45I
PO2SHTC{BtK/WHT)
PO2SHTCIALK/WHTI
ECM CONNECTOR
female terminals
11-162
\.
!
\
A {32P}
o
6I9l roIt
12t3l5t61't8t9a221 232a
252'2aEito,1| ---
The scan tool indicates Diagnostic Trouble Code (DTC) Pl167: A system malfunction in the Primary Heated
Orygen Sensor {Primary HO2S) (Sensor 1) Heater circuit
PRIMABY HO2S ISENSOR 1} 8P CONNECTOR
tc145l
ECM CONNECTOR C (31P)
- The MIL has be€n reported on.- DTC Pl167 i3 3tored.
Problem Veritication:1. Do the ECM Reset Procedure.
2. Start the engine. Hold the
engine at 3,000 mm with no
load (transmission in neutral)
until the radiator fan comes
on.Intormittont failure, system i3 OK
at thia time. Chock for Poor con_
noction3 or looso wilgt ai Cl45(Primary HO2S, Son3or 1l andECM.
ls DTC1167 indicated?
Check lor sn open in the wire(VS+ linel:1. Turn the ignition switch OFF
2. Disconnect the Primary HO2S
{Sensor 1) 8P connector.
3. Turn the ignition switch ON (ll).
4. Measure voltage betwe€n thePrimary HO2S (Sensor '1) 8P
connector terminal No 6 and
body ground.
Ch.ck the ECM:Measure voltage between the
ECM connector terminsl C25 and
body ground.
ls there more than 5 V?
Repair opon in the wite ECM (C25)
and P m.ry HO2S (S€n3or 11.ls there more than 5 V?
Replaco the Primary HO2S (Son-
sor 11.Substitute ! known-good ECM
and r6check. lf symptom/indica-tion gos6 away, r.place tho origi'
nd ECM,
,l23458910
111213t415161718
a2125a30
VS+{WHTIWire side of femaleterminals
1 1-163
PGM-FI System
Fuel Supply System
D017-il Th""""ntool indicates Diagnostic Troubte Code {DTC) p0171;Thefuet system istoo lean.
1P0172 | fne scan tool indicates Dlagnostic Trouble Code (DTC) P0172:Thefuel system istoo rich.
Description
By monitoring the Long Term Fuel Trim, long term malfunctions in the fuel system will be detected.lf a malfunction has been detected during two consecutive trips, the MIL will come on and DTC P0171 and/or P0172 will bestored.
NOTE: lf some of the DTCS listed below are stored at the same time as DTC P0171 andlot P0172, ltouhleshoot those DTCSfirst. then recheck for DTC P0l7l andlot P0172.
P0106-8, P1128*3. *5, P1129*3 *5 MAP Sensor
P0135; Primary HO2S Heater
P0137. P0138: Secondary HO2S
P0'141: Secondary HO2S Heater
P0401: EGR Flow Insufficient*1
P0441: EVAP System Insufficient Purge Flow*6
P1259: VTEC System*,
P1491:EGR Valve Lift Insufficient*r
P1498: EGR Valve Lift Sensor Hjgh Voltage*r
*r: D16Y5 engines*' : Dl6Y5, D16Y8, 81642 engine*3: '97 models*a:'96 modelsf 5: '98 - 00 models*6: '96 D16Y5 engine,'96 D16Y7 engine,'96 D16Y8 engine (sedan),'97 D16y5 engine,,97 D16y7 engine (coupe: KA, KC mo+els, sedan KA. KC, KL (DX) models. hatchback; all models),'97 D16Y8 engine (sedan: KA, KC models)
Possible Cause
DTC P0'171
loo lean
DTC P0172
too rach
Fuel Pump insuff icient f lovpressure
Fuel Feed Line clogged, leaking
Fuel Pressure Regulator stuck open
Fuel Filter clogged
Fuel Injector clogged, air inclusion
Gasoline doesn't meet Owner's Manual spec.
Primary HO2S (Sensor 1) deteriorated
MAP Sensor range/performance*.
EGR System malfunction (too much flow)*1
Valve Clearance
Exhaust leak
Fuel Pressure Regulator clogged, stuck closed
Fuel Return Pipe clogged
Fuel Injector leaking
Gasoline doesn't meet Owner's Manual spec.Primary HO2S (Sensor 1) deteriorated
MAP Sensor range/performance*a
EGR System insufficient flow*1
EVAP Purge Control Solenoid Valve leaking, stuck opened
Valve Clearance
11-164
PGM-FI System
Random Misfire
lFoioo l*u o, [FTioo l*' *' and
The scan tool indicates Diagnostic Trouble Code (DTC)
P0300*5 or P1300*3 *1 and some of P0301 - P0304:Random misfire.Description
Misfire detection is accomplished by monitoring the crankshaft speed with the crankshaft speed fluctuation (CKF) sensorwhich is attached to the crankshaft.
lf misfiring strong enough to damage the catalyst is detected. the MIL will blink during the time of its occurrence, and DTCP0300*5 or P1300*3'*' and some of DTCs P0301 through P0304 will be stored. Then, after misfire has ceased, the MIL willcome on.
lf misfiring that increases emissions is detected during two consecutive driving cycles, the MIL will come on, and DTCP0300*5 or P1300*3 *a and some of DTCS P0301 through P0304 will be stored.NOTE: lf some of the DTCS listed below are stored at the same time as a misfire DTC. troubleshoot those DTCS first, thenrecheck for the misfire DTC.
P0106*4. P0107. P0108, P1128*3 *5, Pl129*3 *5; MAP sensorP0131. P0132: HO2S
P0171, P0112i Fuel metering
P0401, P 1491, P1498: EGR svstem*1P0505: ldle Control SystemP1253: VTEC System*,P1361, P1362: TDC sensorP1381, Pl382: CYP sensorP1508: IAC valve
Possible Cause. Fuel pump insufficient fuel pressure, amount of flow. Fuel line clogging, blockage, leakage. Fuel filter clogging. Fuel pressure regulator stuck open. EGR system malfunction*1. Distributormalfunction. lgnition coil wire open. leakage *l: D16Y5 engine. lgnition control module malfunction *2: D16Y5, D16Y8, Bt6A2 engine. MAP sensor range/performance, poor response*r *3: '97 models. Valves carbon deposit *4;'96 models. Compression low *5: '98 - 00 models. IAC valve malfunctionr.. VTEC system malfunction*,. Fuel does not meet Owner's Manual spec., lackoffuel. HO2S. HO2S circuit
Troubleshooting
By test-driving, determine the conditions during which misfire occurs, Depending on these conditions, test in the orderdescribed in the table below.
Possible
- --^ ---
rage
causeEGR*1
system
Crankshaft
position (CKP)
sensor
Fuel
pressure
Distributor and
lgnition wirestcMClearance
tAc
ValveMAP
sensor
section 611-230,
231section 23section 23section 611-19411
Only low rpm and
loado@@oo
Only accelerating@o@@
Only high rpm and
toaooo@
Not specificoo@
NOTE: lf misfire doesn't recur, some possible causes are fuel that doesn't meet owne/s manualspec, lack of fuel, carbon deposits on spark plug, etc.
1 1-1 66
I
P0304
PGM-FI System
Knock Sensor (KSl ('96 - 98 D16Y5 engine with CW and'96 - 98 D16Y8
engine)
Forr-l I,3,.""""
tool indicates Diagnostic Trouble Code (DTC) P0325: A malfunction in the circuit of the Knock sensor
DIAPHRAGM
ECM/PCM CONNECTOR D {16PI
KS 2P CONNECTOR (Cl371
KS(RED/BLUI
KSIRED/BLU)
The MIL has bgen roportsd on.DTC PO:t25 is stored.
Problom veiilication:1. Do the ECM/PCM Reset Proce-oure,2. Start the engine. Hold theengine at 3,000 rpm with noload (in Park or neutral) untilthe radiator tan comes on,then let it idle.3. Hold the engine at 3,000 -
4,000 rpm tor at least 60 sec-onds.
Intermittenl fsilu16, 3y3l6m b OKat thi3 timg lteat drivo mav banoc63saryl.Chock tor poor conneclioni orloose wire3 b€twccn C137 {knocklen3or (KS)l and ECM/PCM.
ls DTC P0325 indicated?
Check for a short in tho wire {KSlinel:1. Turn the ignition switch OFF.2. Disconnect the knock sensor2P connector,3. Discon n ect the ECM/PCMconnector O (16P).
4. Check for continuity betweenECM/PCM connector termi-nals D6 and body ground.
Reo.ir 3hort in the wire betweenECM/PCM {DG) .nd knock 3.n-
Chock for an open in the wire(KS linel:Check for continuity betweenECM/PCM connector torminal D6and knock sensor 2P connectorterminal No. l.
Ropair open in the wire bgtweonECM/PCM lD6l and knock sen-3('t.ls there continuity?
Substitute a known-good knocksensor and recheck.
Rsplace th. o.igin.l knock s€nsor.
Substitute a known-good ECM/PCM end recheck. lf 3ymptom/indication goes rway, replacerhe original ECM/PCM.
Wire side of female terminals
1\
I
tert
,_-
eslnini
,--tl
le oI temrlsal€
121
189't01t12
13l4t5t6
11-170
Knock sensor (Ks) r99 - 00 D16Y5 engine with cw, '99 - 00 D16Y8 engine and
816A2 engine
The scan tool indicates Diagnostic Trouble Code (DTC) P0325: A malfunction in the circuit of the Knock Sensor
{KS}.
OIAPHRAGM
ECM/PCM CONNECTOR C (31P)
KS 2P CONNECTOR (C1371
KS
Wire side of female terminals
t
The MIL has been reported on.
DTC m325 is stored
Problem verification:1. Do the ECM/PCM Reset Pro
cedure,2. 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.
3. Hold the engine at 3.000 -
4,000 rpm for at least 60 sec'
onds.
lntermittent failure, system is OK
at thi3 time lt€3t drive maY b€
nocessaryl.Chsck tor poor connections or
loose wiros at C137 {knock sen'
sor {KSll and ECM/PCM.
ls DTC P0325 indicated?
Ch€ck for a short in tho wire (KS
linel:1. Turn the ignition switch OFF.
2, Disconnect the knock sensor
1P connector.3. Check for continuity between
ECM/PCM connector termi_
nals C3 and body ground.
Repri. short in the wiro bqtwecnECM/PCM lc3l and knock 3ensor.ls there continuity?
Check for an open in lhe wire
{KS linc):Check for continuity between
ECM/PCM connector terminal C3
and knock sensor connector ter-
minal No. 1.
Replir open in the wire bdtweon
ECM/PCM {Ctl and knock sensor'
SubstitLrte a known'good knock
sensor and recheck,
Replace tho otiginal knock sensor.
substitute a known-good ECM/PCM and recheck. ll symptom/indication goes awaY, rePl6co
tha o.iginal ECM/PCM.
Wire side of female terminals
ECM/PCM CONNECTOR
11-171
(From page | 1-172)
Check fo. a sho.t in the CKP/
TDC/CYP sensor:Check for continuity to bodYground on both terminals of the
indicated senso r individually
1*see table).
Replaco the di3tributor ignition
hoGing lsee section 23).ls there continuity?
Check for an open in the wires
ICKP/TOC/CYP line3):1. Reconnect the distributor 10P
connecaor.2. Disconnect the EcM/PCM con-
nector C {31P}.3. N4easure resistance betweenthe terminals of the indicated
sensor on the ECIM/PCM con-
nector {*see tabie}.
Repair open in the indicated sen-
sor wires lrsee tablel.ls there 350 - 700 o?
Chock lor. short in the wires
ICKP/TDC/CYP lines):
Check for continuity between
body ground and ECM/PCM con-
nector terminals C2, C3 and/or C4individually.
Repai. short in the indic.ted sen_
sor wire3 ('soe tablol,ls there continuity?
Substitute e known-good ECM/PCM, and iecheck. ll sYmptom/indication goes awev, r€Place the
original ECM/PCM.
DISTRIBUTOR10P CoNNECTOR {C1201
Terminalside ofmale terminals
ECM/PCM CONNECTORS C 131P)
CI(P P TDC P CYP P(YEL)
M
CKP M(WHT)MIBLKI
Wire side offemale terminals
CYP PIYELI
(REDI
TDC P(GRN)CKP P(BLU}
t
TDC P (GRNI
11-173
Dl6Y5.816A2 engine:
DISTRIEUTOR
Terminal side olmale terminals
016Y7, Dt6Y8 engine:
DISTRIBUTOR8P CONNECTOR (Cl201
Terminal side olmale terminals
CKP MIWHT}
lDC M(REDI
ECM/PCM CONNECTORc l31P)
wire side of female terminals
t
l0P coNNECTOR {C120)(From page 11-174)
Chock for.3hort in lho CKP/
Tlrc s6n3o.:
Check {or continuity to body
ground on both tsrminals of the
indicated sensor individuallY.
Chsck for an open in the wile3
ICKP/TIrc line6l:1. R€connect the CKP/TDC son-
sor 4P connector.2. Disconnect the ECM/PCM con-
nector C 131P).3. Measure resistance between
the terminals ol the indicated
sensor on the ECM/PCM con-
nector 1*see tablel.
Ropsir opon in tho indiclted son-ior wiro3 l*!sa tabla).ls there 350 - 700 o?
Chack for a .ho in th6 wiros
{CKP/TDC lino3l:Check for continuity between
body ground and ECM/PCM con-
nector terminals C8, C20 and/or
C29 individually.
Rcpair rhort in th. indicat.d 36n_
lor wirar {'3ac trblol.
Substituto . known-good ECM/
PCM lnd rechock. lf 3ymptom/indicatlon go6s aw.y, ropllc.tho origin.l ECM/PCM.
ECM/PCM CONNECTOR C (31P)
Wire side of femsle terminals
CKP P
11-175