1996 ACURA RL KA9 sensor

Heated Oxyge n Senso r (HO2S ) Heate r
The sca n too l indicate s Diagnosti c Troubl e Cod e (DTC ) P0135 : A proble m in th e Righ t Primar y Heate d Oxyge n
Sensor (Righ t Primar y HO2S ) (Ban k 1 , Senso r 1 ) Heate r circuit .
The sca n too l indicate s Diagnosti c Troubl e Cod e (DTC ) P0141 : A proble m in th e Secondar y Heate d Oxyge n
Sensor (Secondar y HO2S ) (Senso r 2 ) Heate r circuit .
The sca n too l indicate s Diagnosti c Troubl e Cod e (DTC ) P0155 : A proble m in th e Lef t Primar y Heate d Oxyge n
Sensor (Lef t Primar y HO2S ) (Ban k 2 , Senso r 1 ) Heate r circuit .
— Th e MI L ha s bee n reporte d on .
— DT C P0135 , P014 1 and/o r
P015 5 ar e stored .
Proble m verification :
1 . D o th e PC M Rese t Procedure .
2 . Star t th e engine .
I s DT C P0135 , P014 1 o r P015 5
indicated ?
YES
Chec k fo r a n ope n o r shor t i n th eHO2S :1. Tur n th e ignitio n switc h OFF .2. Disconnec t th e righ t primar y
HO2 S (Ban k 1 , Senso r 1) , sec -
ondar y HO2 S (Senso r 2)*
1 o rleft primar y HO2 S (Ban k 2 ,Senso r 1 )*2 connector .
3 . Measur e resistanc e betwee n
th e 4 P connecto r No . 3 an d
No . 4 terminal s o n th e HO2 S
side .
Is there 10 - 40 ?
YE S
Chec k fo r continuit y t o bod y
groun d o n HO2 S terminal s No . 3
termina l an d No . 4 individually .
Is ther e continuity ?
NO
Chec k fo r a n ope n o r shor t i n th e
wire s H G 1, O2SHT C lines) :
1. Tur n th e ignitio n switc h O N (II) .2. Measur e voltag e betwee n No .
3 termina l an d No . 4 termina l
o n th e harnes s sid e o f th e 4 P
connector . RIGH
T PRIMAR Y HO2 S (Ban k 1 , Senso r 1 ) CONNECTOR ,
LEF T PRIMAR Y HO2 S (Ban k 2 , Senso r 1 ) CONNECTOR *
SECONDAR Y HO2 S (Senso r 2 ) CONNECTOR*
1
N O
Intermitten t failure , syste m is O K
a t thi s time . Chec k fo r poo r con -
nection s o r loos e wire s a t C251 ,
C25 3 (locate d a t lef t shoc k tower) ,
C442 , C44 4 (locate d behin d righ t
kic k panel)*
1, C11 9 (righ t primar y
HO2 S (Ban k 1 , Senso r 1)) , C61 0
(secondar y HO2 S (Senso r 2))*
1 o r
C12 6 (lef t primar y HO2 S (Ban k 2 ,
Senso r 1)*
2 an d PCM . Termina
l sid e o f mal e terminal s
Replac e th e HO2S .
Replac e th e HO2S .
RIGHT PRIMAR Y HO2 S (Ban k 1 , Senso r 1 ) CONNECTO R (C119) ,
LEF T PRIMAR Y HO2 S (Ban k 2 , Senso r 1 ) CONNECTO R (C126)*
2
SECONDAR Y HO2 S (Senso r 2 ) CONNECTO R (C610)*1
Is ther e batter y voltage ?YES
NO
(T o pag e 11-92 ) (T
o pag e 11-92 ) Wir
e sid e o f femal e terminal s*1: P014 1*2: P015 5
YES
NO
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Fuel Supply System

Description

By monitoring the Long Term Fuel Trim, long term malfunctions in the fuel system will be detected.

If a
malfunction
has
been detected during
two
consecutive
trips,
the MIL
will
come
on and DTC
P0171, P0172,
P0174

and/or P0175 will be stored.

NOTE: If some of the DTCs listed below are stored at the same time as DTC P0171, P0172, P0174 and/or P0175, trou-

bleshoot those DTCs first, then troubleshoot DTC P0171, P0172, P0174 and/or P0175.

P0106*1, P0107, P0108, P1128*2, P1129*2: MAP Sensor

P0135: Right Primary HO2S Heater (Bank 1, Sensor 1)

P0137, P0138: Secondary HO2S (Sensor 2)

P0141: Secondary HO2S Heater (Sensor 2)

P0155: Left Primary HO2S Heater (Bank 2, Sensor 1)

P0401: EGR Flow Insufficient

P1491: EGR Valve Lift Insufficient

P1498: EGR Valve Position Sensor High Voltage

*1: '96 model only

*2: '97 - 01 models

DTC P0172, P0175

System too rich
• Fuel Pump insufficient flow/pressure

• Fuel Feed Line clogged, leaking

• Fuel Pressure Regulator stuck open

• Fuel Filter clogged

• Injector clogged, air inclusion

• Gasoline doesn't meet Owner's Manual spec.

• Primary HO2S (Sensor 1) deteriorated

• MAP Sensor range/performance*1

• EGR System insufficient flow

• Exhaust leak

• Fuel Pressure Regulator clogged, stuck closed

• Fuel Return Pipe clogged

• Injector leaking

• Gasoline doesn't meet Owner's Manual spec.

• Primary HO2S (Sensor 1) deteriorated

• MAP Sensor range/performance*1

• EGR System malfunction (too much flow)

• EVAP Canister Purge Valve leaking, stuck opened
DTCP0171, P0174

System too lean
The scan tool indicates Diagnostic Trouble Code (DTC) P0171: The fuel system is too lean [Right Bank (Bank 1)].

The scan tool indicates Diagnostic Trouble Code (DTC) P0172: The fuel system is too rich [Right Bank (Bank 1)].

The scan tool indicates Diagnostic Trouble Code (DTC) P0174: The fuel system is too lean [Left Bank (Bank 2)].

The scan tool indicates Diagnostic Trouble Code (DTC) P0175: The fuel system is too rich [Left Bank (Bank 2)].

Possible CauseProCarManuals.com

PGM-FI System

Fuel Supply System (cont'd)

— The MIL has been reported on.

— DTC P0171, P0172, P0174 and/

or P0175 are stored.

Check the fuel pressure.

Is the fuel pressure OK?
NO

YES

Check the Primary HO2S:

1. Start the engine. Hold the

engine at 3,000 rpm with no

load (in Park or neutral) until

the radiator fan comes on.

2. Check the right primary or left

primary* HO2S (Sensor 1) out-

put with the scan tool.
Is the fuel pressure too high

or too low?
Check the fuel pressure regulator

and fuel return pipe.

LOW

Check the fuel pump, fuel feed

pipe, fuel filter, and fuel pressure

regulator.

Does it stay at less than 0.3 V

or more than 0.6 V?
Replace the HO2S.

NO

Check for a sticking or leaking

EVAP canister purge valve:

With a vacuum pump, apply vacu-

um to the EVAP canister purge

valve from the intake manifold

side.

Does it hold vacuum?

('96 model only)
Replace the EVAP canister purge

valve.

YES

Check the MAP sensor output:

1. Turn the ignition switch ON (II).

2. Check the MAP with the scan

tool.

Does it indicate atmospheric

pressure?
YES

*: P0174 or P0175
Check the response of the MAP

sensor:

1. Start the engine.

2. Check the MAP with the scan

tool.

Is a MAP of 40.0 kPa (300 mmHg,

12.0 inHg) or less indicated within

one second after starting the

engine?
Replace the MAP sensor.

YES

Check the EGR system. If it is OK,

replace the fuel injectors.
NO
NO

Replace the MAP sensor.
NO
YES
HIGH
Troubleshooting FlowchartProCarManuals.com

The sca n too l indicate s Diagnosti c Troubl e Cod e (DTC ) P0325 : A proble m in th e Righ t Knoc k Senso r (Ban k 1 ) cir -
cuit .
The sca n too l indicate s Diagnosti c Troubl e Cod e (DTC ) P0330 : A proble m in th e Lef t Knoc k Senso r (Ban k 2 ) cir -
cuit .
— Th e MI L ha s bee n reporte d on .
— DT C P032 5 and/o r P033 0 ar e
stored .
Proble m verification :1. D o th e PC M Rese t Procedure .2. Star t th e engine . Hol d th eengin e a t 3,00 0 rp m wit h n oloa d (i n Par k o r neutral ) unti l
th e radiato r fa n come s on ,
the n le t i t idle .
3 . Hol d th e engin e a t 3,00 0 -
4,00 0 rp m fo r 1 0 seconds .
Is DT C P032 5 and/o r P033 0indicated ?
YES
Chec k fo r a shor t i n th e wir e
(knoc k senso r line) :
1 . Tur n th e ignitio n switc h OFF .
2 . Disconnec t th e knoc k senso r
sub-harnes s connector .
3 . Chec k fo r continuit y betwee n
PC M connecto r terminal s D 2
o r D13 * an d bod y ground .
I s ther e continuity ?
NO
Chec k fo r a n ope n i n th e wir e
(knoc k senso r line) :
Chec k fo r continuit y betwee n PC M
connecto r termina l D 2 o r D13 *
an d knoc k senso r connecto r ter -
mina l No . 1 o r No . 3* .
I s ther e continuity ?
YES
Substitut e a known-goo d righ t o r
lef t knoc k senso r an d recheck .
I s DT C P032 5 and/o r P033 0
indicated ?
YES
Substitut e a known-goo d PC M
an d rechec k (se e pag e 11-42 fo r
immobilize r information) . I f symp -
tom/indicatio n goe s away , replac e
th e origina l PCM .
NO
Intermitten t failure , syste m is O K
a t thi s tim e (tes t driv e ma y b e
necessary) . Chec k fo r poo r con -
nection s o r loos e wire s betwee n
C25 1 (locate d a t lef t shoc k
tower) , C11 0 (locate d a t lef t rea r
corne r o f engine) , C162* , C16 3
(knoc k sensor ) an d PCM .
PCM CONNECTO R D (22P )
Repai r shor t i n th e wir e betwee n
PC M (D 2 o r D13* ) an d knoc k sen -
sor.
Wir e sid e o f femal e terminal s
Repai r ope n in th e wir e betwee n
PCM (D 2 o r D13* ) an d knoc k sen -sor.
KNOC K SENSO RCONNECTO RReplace th e origina l knoc k sensor .
Wire sid e o f femal e terminal s
*: P033 0
NO
N
O
YE S
Knoc k Senso r
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PGM-FI System

Misfire Detected in One Cylinder

The scan tool indicates Diagnostic Trouble Code (DTC) P1203 or P1303: Cylinder 3 misfire detected.

The scan tool indicates Diagnostic Trouble Code (DTC) P1204 or P1304: Cylinder 4 misfire detected.

The scan tool indicates Diagnostic Trouble Code (DTC) P1205 or P1305: Cylinder 5 misfire detected.

Description

Misfire detection is accomplished by monitoring the voltage of the spark plug with the spark plug voltage sensor which is

built into the ignition coil.

If misfiring strong enough to damage the catalyst is detected, the MIL will blink during the time of its occurrence, and a

misfire DTC will be stored. Then, after the misfire has ceased, the MIL will come on and stay on whenever the ignition

switch is ON (II).

If misfiring that increases emissions is detected during two consecutive driving cycles, the MIL will come on, and a misfire

DTC will be stored.

NOTE: If some of the DTCs listed below are stored at the same time as a misfire DTC, troubleshoot those DTCs first, then

troubleshoot the misfire DTC.

P0106*1, P1128*2, P1129*2: MAP sensor

P0171, P0172, P0174, P0175: Fuel supply system

P0401, P1491, P1498: EGR system

P1316, P1317, P1318, P1319: Spark Plug Voltage Detection System

P0335, P0336, P1336, P1337: CKP sensor

P1381, P1382, P1386, P1387: CYP sensor

*1: '96 model only

*2: '97 - 01 models

Possible Cause

Injector clogging, fuel leakage, air leakage

Injector circuit open or shorted

Injector resistor malfunction

Spark plug carbon deposits, fouling, malfunction

Ignition coil malfunction

ICM malfunction

Compression low
or

The scan tool indicates Diagnostic Trouble Code (DTC) P1206 or P1306: Cylinder 6 misfire detected.
or
or
or
The scan tool indicates Diagnostic Trouble Code (DTC) P1201 or P1301: Cylinder 1 misfire detected.

The scan tool indicates Diagnostic Trouble Code (DTC) P1202 or P1302: Cylinder 2 misfire detected.
or
orProCarManuals.com

PGM-FI Syste m
Crankshaf t Position/Cylinde r Positio n (CKP/CYP ) Senso r
The sca n too l indicate s Diagnosti c Troubl e Cod e (DTC ) P0335 : A malfunctio n in th e circui t o f th e Crankshaf t
Positio n (CKP ) senso r 1 .
Th e sca n too l indicate s Diagnosti c Troubl e Cod e (DTC ) P0336 : A n intermitten t interruptio n proble m of the
Crankshaf t Positio n (CKP ) senso r 1 .
Th e sca n too l indicate s Diagnosti c Troubl e Cod e (DTC ) P1337 : A malfunctio n i n th e circui t o f th e Crankshaf t
Positio n (CKP ) senso r 2 .
Th e sca n too l indicate s Diagnosti c Troubl e Cod e (DTC ) P1336 : A n intermitten t interruptio n proble m o f th e
Crankshaf t Positio n (CKP ) senso r 2 .
Th e sca n too l indicate s Diagnosti c Troubl e Cod e (DTC ) P1381 : A n intermitten t interruptio n proble m o f th e
Cylinde r Positio n (CYP ) senso r 1 .
Th e sca n too l indicate s Diagnosti c Troubl e Cod e (DTC ) P1382 : A malfunctio n in th e circui t o f th e Cylinde r Positio r
(CYP ) senso r 1 .
Th e sca n too l indicate s Diagnosti c Troubl e Cod e (DTC ) P1386 : A n intermitten t interruptio n proble m of the
Cylinde r Positio n (CYP ) senso r 2 .
Th e sca n too l indicate s Diagnosti c Troubl e Cod e (DTC ) P1387 : A malfunctio n in th e circui t o f th e Cylinde r Positio n
(CYP) senso r 2 .
Proble m verification :
1 . D o th e PC M Rese t Procedure .
2 . Star t th e engine .
I s DT C P0335 , P0336 , P1337 , P1336 ,
P1381 , P1382 , P138 6 and/o r P138 7
indicated ?
Chec k fo r a n ope n in th e CKP/CY P
sensor:1. Tur n th e ignitio n switc h OFF .2. Disconnec t th e CKP/CY P 8 P
connector .
3 . Measur e resistanc e betwee n
the terminal s o f th e indicate dsensor (se e table) .
I s ther e 65 0 - 85 0
YES
Chec k fo r a shor t i n th e CKP/CY Psensor:Check fo r continuit y t o bod yground o n bot h terminal s o f th eindicate d sensor . CY
P PICK-U P
COI L 2
CY P PICK-U P
COI L 1
Intermitten t failure , syste m is O K
a t thi s time . Chec k fo r poo r con -
nection s o r loos e wire s a t C251 ,
C25 5 (locate d a t lef t shoc k tower) ,
C13 0 (CKP/CYP ) senso r an d PCM .
Replac e th e CKP/CY P senso r (se e
sectio n 6 ).
CKP/CYP SENSO R 8 P CONNECTO R
Termina l sid e o f mal e terminal s
(T o pag e 11-107 )
NO
YE S
NO
CK P PICK-U P
COI L 1CK P PICK-U PCOIL 2
Th e CK P Senso r determine s timin g fo r injectio n an d ignitio n o f eac h cylinde r an d als o detect s engin e speed .
Th e CY P Senso r detect s th e positio n o f No . 1 cylinde r fo r sequentia l injectio n t o eac h cylinder . Th e CKP/CY P Senso r i s
installe d behin d th e fron t camshaf t pulley .
— Th e MI L ha s bee n reporte d on .
— DT C P0335 , P0336 , P133 7
P1336 , P1381 , P1382 , P138 6
and/o r P138 7 ar e stored .
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Idle Contro l Syste m
System Descriptio n
The idl e spee d o f th e engin e is controlle d b y th e Idl e Ai r Contro l (IAC ) Valve .
Th e valv e change s th e amoun t o f ai r bypassin g int o th e intak e manifol d i n respons e t o electri c curren t controlle d b y th e
PCM . Whe n th e IA C Valv e is activated , th e valv e open s to maintai n th e prope r idl e speed .
VARIOU S
SENSOR S
INTAK E
MANIFOL D
IDLEADJUSTIN GSCREW
1. Afte r th e engin e starts , th e IA C valv e open s fo r a certai n time . Th e amoun t o f ai r i s increase d t o rais e th e idl e spee d
abou t 15 0 - 30 0 rpm .
2 . Whe n th e coolan t temperatur e i s low , th e IA C valv e i s opene d t o obtai n th e prope r fas t idl e speed . Th e amoun t o f
bypasse d ai r i s thu s controlle d in relatio n to th e engin e coolan t temperature .
3 . Whe n th e idl e spee d is ou t o f specificatio n an d th e sca n too l doe s no t indicat e Diagnosti c Troubl e Cod e (DTC ) P050 5 o r
P1508 , chec k th e followin g items :
• Adjus t th e idl e spee d (se e pag e 11-124 )
• Ai r conditionin g signa l (se e pag e 11-116 )
• AL T F R signa l (se e pag e 11-118 )
• Starte r switc h signa l (se e pag e 11-119 )
• Transmissio n rang e signa l (se e sectio n 14 )
• PS P switc h signa l (se e pag e 11-120 )
• Brak e peda l positio n switc h signa l (se e pag e 11-122 )
• Idl e ai r contro l therma l valv e (se e pag e 11-123 )
• Hose s an d connection s
• IA C valv e an d it s mountin g O-ring s
4 . I f th e abov e item s ar e normal , substitut e a known-goo d IA C valv e an d readjus t th e idl e spee d (se e pag e 11-124 ).
I f th e idl e spee d stil l canno t b e adjuste d t o specificatio n (an d th e sca n too l doe s no t indicat e DT C P050 5 o r P1508 ) afte r
IA C valv e replacement , substitut e a known-goo d PC M an d rechec k (se e pag e 11-42 fo r immobilize r information) . I f
sympto m goe s away , replac e th e origina l PCM .
IDLEAIRCONTRO LTHERMA LVALVE
IAC VALV E
FromPGM-F IMAINRELA Y
ENGIN E COOLAN T
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Injectors
Replacemen t
9.8 N- m(1.0 kgf-m , 7. 2 Ibf-ft )
Do no t smok e whe n workin g o n th e fue l system . Kee p ope n flame s awa y fro m you r wor k area .
1 . Remov e th e stru t bar .
2 . Remov e th e engin e cover .
3 . Reliev e fue l pressur e (se e pag e 11-132 ).
4 . Disconnec t th e connector s fro m th e injectors .
5 . Disconnec t th e PC V valve .
6 . Disconnec t th e vacuu m hos e an d fue l retur n hos e fro m th e fue l pressur e regulator .
NOTE : Plac e a ra g o r sho p towe l ove r th e hose s befor e disconnectin g them .
7. Disconnec t th e fue l hos e fro m th e fue l rail .
8 . Remov e th e vacuu m pipe .
9 . Loose n th e retaine r nut s o n th e fue l rai l an d harnes s holder .
10 . Disconnec t th e 3 P connecto r fro m th e MA P sensor .
11 . Disconnec t th e fue l rail .
12 . Remov e th e injector s fro m th e intak e manifold .
HARNESSHOLDER
SEALRINGReplace .
FUELPRESSUR EREGULATO R
INJECTO R
INSULATO R
PCVVALV E
MAPSENSO R
O-RINGReplace .
CUSHIONRINGReplace .
INJECTO R
12 N- m(1.2 kgf-m ,
8. 7 Ibf-ft )
ENGIN ECOVER
9.8 N- m(1.0 kgf-m , 7. 2 Ibf-ft )
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