1995 ACURA TL ECO mode

'97 - 98 models:

LEFT PRIMARY HEATED OXYGEN SENSOR (LEFT PRIMARY

HO2S) (BANK 2 SENSOR 1)

RIGHT PRIMARY HEATED OXYGEN SENSOR (RIGHT

PRIMARY HO2S) (BANK 1 SENSOR 1)

SECONDARY HEATED OXYGEN SENSOR (SECONDARY

HO2S) (SENSOR 2)

MANIFOLD ABSOLUTE PRESSURE (MAP) SENSOR

INTAKE AIR TEMPERATURE (IAT) SENSOR

LEFT KNOCK SENSOR (LEFT KS) (BANK 2)

RIGHT KNOCK SENSOR (RIGHT KS) (BANK 1)

IDLE AIR CONTROL (IAC) VALVE

FAST IDLE THERMO VALVE

IDLE ADJUSTING SCREW

FUEL INJECTOR

FUEL PRESSURE REGULATOR

FUEL PRESSURE REGULATOR CONTROL SOLENOID VALVE

FUEL FILTER

FUEL PUMP (FP)

FUEL TANK

AIR CLEANER (ACL)

INTAKE AIR BYPASS (IAB) LOW CONTROL DIAPHRAGM

VALVE

INTAKE AIR BYPASS (IAB) LOW CONTROL SOLENOID

VALVE

INTAKE AIR BYPASS (IAB) HIGH CONTROL DIAPHRAGM

VALVE

INTAKE AIR BYPASS (IAB) HIGH CONTROL SOLENOID

VALVE
INTAKE AIR BYPASS (IAB) VACUUM TANK

INTAKE AIR BYPASS (IAB) CHECK VALVE

THREE WAY CATALYTIC CONVERTER (TWC)

EXHAUST GAS RECIRCULATION (EGR) VALVE AND LIFT

SENSOR

EXHAUST GAS RECIRCULATION (EGR) CONTROL

SOLENOID VALVE

EXHAUST GAS RECIRCULATION (EGR) VACUUM CONTROL

VALVE

POSITIVE CRANKCASE VENTILATION (PCV) VALVE

EVAPORATIVE EMISSION (EVAP) PURGE CONTROL

SOLENOID VALVE

EVAPORATIVE EMISSION (EVAP) CONTROL CANISTER

EVAPORATIVE EMISSION (EVAP) THREE WAY VALVE

EVAPORATIVE EMISSION (EVAP) CONTROL CANISTER

VENT SHUT VALVE

EVAPORATIVE EMISSION (EVAP) TWO WAY VALVE

EVAPORATIVE EMISSION (EVAP) BYPASS SOLENOID

VALVE

FUEL TANK PRESSURE SENSOR

FUEL TANK EVAPORATIVE EMISSION (EVAP) VALVE

WATER VALVE CONTROL SOLENOID VALVE

WATER VALVE CONTROL DIAPHRAGM

WATER VALVE CHECK VALVE

FUEL PULSATION DAMPERProCarManuals.com

DTC(MI L indication )
P0325 (53 )
P033 0 (23 )
P033 5 (4 )
P033 6 (4 )
P040 1 (80 )
P042 0 (67 )
P0441 (92)*2
P045 2 (91 )
P0453 (91 )
P050 5 (14 )
P0700P0715
P072 0
P0730
P074 0P0753
P075 8
P1106 (13)*3
P110 7 (13 )
P110 8 (13 )
Detection Ite m
Righ t Knoc k Senso r (Ban k 1 )
Circui t Malfunctio n
Left Knoc k Senso r (Ban k 2 )
Circui t Malfunctio n
Crankshaft Positio n
Senso r 1 Circui t
Malfunctio n
Crankshaf t Positio n
Senso r 1
Range/Performanc e
Exhaust Gas Recirculatio n
Insufficien t Flo w Detecte d
Catalys t Syste m
Efficienc y Belo w
Threshol d
Evaporativ e Emissio n Contro l
Syste m
Incorrec t Purg e Flo w
Evaporativ e Emissio n Contro l
Syste m Pressur e Senso r (Fue l Tan k
Pressur e Sensor ) Circui t Lo w Inpu t
Evaporativ e Emissio n Contro l
Syste m Pressur e Senso r (Fue l Tan k
Pressur e Sensor ) Circui t Hig h Inpu t
Idle Contro l Syste mMalfunctio n
Automatic
Transaxle
Barometri c
Pressur e Circui t
Range/Performanc e Proble m
Barometri c
Pressur e Circui t
Range/Performanc e Proble m
Barometri c
Pressur e Circui t
High Inpu t
Probabl e Caus e
• Ope n o r shor t i n Righ t Knoc k Senso r
(Ban k 1 ) circui t
• Righ t Knoc k Senso r (Ban k 1 )
• PC M
• Ope n o r shor t i n Lef t Knoc k Senso r
(Ban k 2 ) circui t
• Lef t Knoc k Senso r (Ban k 2 )
• PC M
• Crankshaf t Positio n Senso r 1
• Crankshaf t Positio n Senso r 1 circui t
• PC M
• Crankshaf t Positio n Senso r 1
• Timin g bel t skippe d teet h
• EG R valv e
• EG R lin e
• Thre e Wa y Catalyti c converte r
• Secondar y HO2 S
• EVA P Purg e Contro l Solenoi d valv e
• EVA P Purg e Contro l Solenoi d valv e circui t
• EVA P Purg e Flo w Switc h
• EVA P Purg e Flo w Switc h circui t
• Throttl e Bod y (purg e port )• Tubin g
• PC M
• Ope n o r shor t i n Fue l Pressur e Senso r
circuit• Fue l Tan k Pressur e Senso r
• PC M
• Ope n in Fue l Tan k Pressur e Senso r circui t
• Fue l Tan k Pressur e Senso r
• PC M
• IA C valv e
• Fas t idl e therm o valv e
• Throttl e Bod y
• PC M (Bar o sensor )
• PC M (Bar o sensor )
• PC M (Bar o sensor )
Page
11-8 4
11-8 4
11-9 4
11-9 4
11-14 7
11-145
11-155
11-15 7
11-15 9
11-10 1
Sectio n 1 4
11-9 6
11-97
11-9 7
*2: '9 6 mode l
*3: '9 7 - 9 8 model s
*5: Th e indicato r ligh t an d th e Malfunctio n Indicato r Lam p (MIL ) ma y com e o n simultaneously .
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PGM-FI Syste m
System Descriptio n
INPUTS POWERTRAI N CONTRO L MODUL E (PCM ) OUTPUT S
Fue l Injector s
PGM-F I Mai n Rela y (Fue l Pump )
MILIAC Valv eA/C Compresso r Clutc h Rela yICMEVA P Purg e Contro l Solenoi dValveLeft Primar y HO2 S Heate r
Righ t Primar y H02 S Heate r
Secondar y HO2 S Heate r
EG R Contro l Solenoi d Valv e
Fue l Pressur e Regulato r
Contro l Solenoi d Valv e
IA B Lo w Contro l Solenoi d Valv e
IA B Hig h Contro l Solenoi d Valv e
EVA P Bypas s Solenoi d Valve*
2
EVA P Contro l Caniste r Ven t Shu t
Valve*2
*1:'9 6 mode l
*2:'97 - 9 8 model s
PGM-F I Syste m
Th e PGM-F I syste m o n thi s mode l i s a sequentia l multipor t fue l injectio n system .
Fue l Injecto r Timin g an d Duratio n
Th e PC M contain s memorie s fo r th e basi c discharg e duration s a t variou s engin e speed s an d manifol d pressures . Th e
basi c discharg e duration , afte r bein g rea d ou t fro m th e memory , i s furthe r modifie d b y signal s sen t fro m variou s sensor s
t o obtai n th e fina l discharg e duration .
Idl e Ai r Contro l
Whe n th e engin e is cold , th e A/ C compresso r i s on , th e transmissio n i s i n gear , th e brak e peda l i s depressed , th e P/ S loa d
i s high , o r th e alternato r i s charging , th e PC M control s curren t t o th e Idl e Ai r Contro l Valv e (IA C Valve ) t o maintai n th e cor -
rec t idl e speed .
Ignitio n Timin g Contro l
Th e PC M contain s memorie s fo r basi c ignitio n timin g a t variou s engin e speed s an d manifol d ai r flo w rates . Ignitio n
timin g i s als o adjuste d fo r engin e coolan t temperature .
A knoc k contro l syste m is als o used . Whe n detonatio n is detecte d b y a knoc k senso r (KS) , th e ignitio n timin g is retarded .
Othe r Contro l Function s
1 . Startin g Contro l
Whe n th e engin e is started , th e PC M provide s a ric h mixtur e b y increasin g fue l injecto r duration .
2 . Fue l Pum p Contro l
Whe n th e ignitio n switc h i s initiall y turne d on , th e PC M supplie s groun d t o th e PGM-F I mai n rela y tha t supplie s cur -
ren t t o th e fue l pum p fo r tw o second s t o pressuriz e th e fue l system .
Whe n th e engin e is running , th e PC M supplie s groun d to th e PGM-F I mai n rela y tha t supplie s curren t t o th e fue l pump .
Whe n th e engin e i s no t runnin g an d th e ignitio n i s on , th e PC M cut s groun d t o th e PGM-F I mai n rela y whic h cut s
curren t t o th e fue l pump .
CKP/CY P Senso rMAP Senso r
EC T Senso r
IA T Senso r
T P Senso r
EG R Valv e Lif t Senso r
Lef t Primar y H02 S
Righ t Primar y HO2 S
Secondar y HO2 S
VSSBAR O Senso rELDLef t K S
Righ t K S
TC S Signal s
Spar k Plu g Voltag e Detectio n Modul e
Signa l
Starte r Signa l
AL T F R Signa l
Air Conditionin g Signa lA/T Gea r Positio n Signa l
Batter y Voltag e (IGN.1 )
Brak e Switc h Signa l
PS P Switc h Signa l
EVA P Purg e Flo w Switch*
1
Fue l Tan k Pressur e Sensor*2
PC M Back-u p Function s
Ignitio
n Timin g Contro l
Othe
r Contro l Function s
Electroni
c idl e Contro l
Fue
l Injecto r Timin g an d Duratio n
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PGM-FI System

System Description (cont'd)

3. 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 1,000 rpm.

Fuel cut-off action also takes place when engine speed exceeds 6,500 rpm, regardless of the position of the throttle

valve, to protect the engine from over-revving.

4. A/C Compressor Clutch Relay .

When the PCM receives a demand for cooling from the air conditioning system, it delays the compressor from being

energized, and enriches the mixture to assure a smooth transition to the A/C mode.

5. Evaporative Emission (EVAP) Purge Control Solenoid Valve

'96 model: When the engine coolant temperature is below 158°F (70°C), the PCM controls the EVAP purge control

solenoid valve which cuts vacuum to the EVAP purge control canister diaphragm.

'97 - 98 models: When the engine coolant temperature is above 99°F (37°C), the PCM controls the EVAP purge control

solenoid valve which controls vacuum to the EVAP purge control canister.

6. Intake Air Bypass (IAB) Low Control Solenoid Valve, Intake Air Bypass (IAB) High Control Solenoid Valve

When engine speed is below 3,350 rpm, the IAB High Control Solenoid Valve and IAB Low Control Solenoid Valve are

activated by a signal from the PCM. Intake air flows through a long chamber path, increasing torque at low RPM.

When engine speed is 3,350 - 3,950 rpm, the IAB Low Control Solenoid Valve is deactivated by the PCM. Intake air

flows through a short chamber path, increasing mid-range torque.

When the engine rpm is above 3,950 rpm, the IAB Low Control Solenoid Valve and IAB High Control Solenoid Valve are

deactivated by the PCM. This creates a very short intake path and increases high-speed torque.

7. Exhaust Gas Recirculation (EGR) Control Solenoid Valve

When the EGR is required for control of oxides of nitrogen (NOx) emissions, the PCM controls the EGR control solenoid

valve which supplies regulated vacuum to the EGR valve.

ECM Fail-safe/Back-up Functions

1. Fail-safe Function

When an abnormality occurs in a signal from a sensor, the PCM ignores that signal and assumes a pre-programmed

value for that sensor that allows the engine to continue to run.

2. Back-up Function

When an abnormality occurs in the 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 [Malfunction Indicator Lamp (MIL)]

When an abnormality occurs in a signal from a sensor, the PCM supplies ground for the MIL and stores the DTC in

erasable memory. When the ignition is initially turned on, the PCM supplies ground for the MIL for two seconds to

check the MIL bulb condition.

4. Two Driving Cycle Detection Method

To prevent false indications, the two driving cycle detection method is used for the H02S, fuel metering-related, idle

control system, ECT sensor, EGR system, TWC, EVAP control system and other self-diagnostic functions. When an

abnormality occurs, the PCM stores it in its memory. When the same abnormality recurs after the ignition switch is

turned OFF and ON (II) again, the PCM informs the driver by lighting the MIL.

However, to ease troubleshooting, this function is cancelled when you short the service check connector. The MIL will

then blink immediately when an abnormality occurs.ProCarManuals.com

PGM-FI Syste m
Powertrai n Contro l Modul e (PCM ) (cont'd )
The Malfunctio n Indicato r Lam p
(MIL ) stay s o n o r come s o n afte r
tw o seconds .
Chec k th e Diagnosti c Troubl e
Code (DTC) :1. Connec t a sca n too l o r Hond a
PG M Tester .
2 . Tur n th e ignitio n switc h O N (II) .
3 . Rea d th e DT C wit h th e sca n
too l o r Hond a PG M Tester .
Are an y DTC(s ) indicated ?
Check th e DT C b y MI L indication :
1 . Tur n th e ignitio n switc h OFF .
2 . Connec t th e SC S servic e con -
necto r t o th e servic e chec k
connector .
3 . Tur n th e ignitio n switc h O N (II) .
Doe s th e MI L indicat e an y DTC ?
Tr y t o star t th e engine .
Doe s th e engin e start ?
NOTE :When ther e is n o Diagnosti c Troubl e Cod e (DTC ) stored , th e MI L wil l sta y o n if th e SC S servic e
connecto r i s connecte d an d th e ignitio n switc h is on .
I f thi s sympto m is intermittent , chec k for :
— A loos e EC U (PCM ) (2 0 A ) fus e in th e under-hoo d fuse/rela y bo x
— A loos e No . 2 FUE L PUM P (1 0 A ) fus e in th e under-das h fuse/rela y bo x
— A n intermitten t shor t i n th e wire betwee n th e PC M (C5 ) an d th e servic e chec k connecto r
— A n intermitten t shor t i n th e wire betwee n th e PC M (A7 ) an d th e gaug e assembl y
— A n intermitten t shor t i n th e wir e betwee n th e PC M (D10 ) an d th e MA P senso r
— A n intermitten t shor t i n th e wire betwee n th e PC M (D21 ) an d th e T P sensor , EG R valv e lif t
sensor , TC S contro l valv e angl e sensor , Fue l tan k pressur e sensor *
Se e th e OB D II sca n too l o r Hond a PG M Teste r user' s manual s fo r specifi c operatin g instruc -
tions.: '9 7 - 9 8 model s
G o to troubleshootin g procedures .
(se e pag e 11-32 )
Repai r ope n o r shor t i n wir e
betwee n the PCM (D4 ) an d
Dat a Lin k Connector .
G o to troubleshootin g proce -
dures . (se e pag e 11-32 )
PCM CONNECTO R C (12P )
Chec k fo r a shor t i n th e wir e (SC S
line) :
1 . Sto p th e engin e an d tur n th e
ignitio n switc h O N (II) .2. Measur e voltag e betwee n th e
PC M connecto r termina l C 5
an d bod y ground . (T
o pag e 11-55 )
Wire sid e o f femal e terminal s
I s ther e approx . 5 V ?
(T o pag e 11-55 ) Repai
r shor t t o bod y groun d in
th e wir e betwee n PC M (C5 ) an d
servic e chec k connector .
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PGM-FI Syste m
Powertrai n Contro l Modul e (PCM ) (cont'd )
(From pag e 11-55 )
Chec k fo r a shor t i n th e wire s
(VC C lines) :
1 . Tur n th e ignitio n switc h OFF .
2 . Disconnec t th e PC M connec -
tor D (22P) .3. Chec k fo r continuit y betwee nbody groun d an d PC M con -necto r terminal s D1 0 an d D2 1individually .
Is ther e continuity ?
I s ther e batter y voltage ?
Chec k fo r a n ope n i n th e wire s
(L G lines) :
1 . Reconnec t al l senso r connec -
tors .
2 . Reconnec t th e PC M connecto r
D (22P) .3. Tur n th e ignitio n switc h O N (II) .
4 . Measur e voltag e betwee n
bod y groun d an d PC M connec -
to r terminal s A2 6 an d B 9 indi -
vidually .
I s ther e les s tha n 1. 0 V ?
Substitut e a known-goo d PC M
an d recheck . I f symptom/indica -
tio n goe s away , replac e th e origi -
nal PCM .
PCM CONNECTO R D (22P )
Repai r shor t t o bod y groun d
i n th e wir e betwee n PC M
(D10 ) an d MA P sensor .Repair shor t t o bod y groun d in
th e wir e betwee n PC M (D21 )
an d EG R valv e lif t sensor , T P
sensor , TC S contro l valv e
angl e senso r o r fue l tan k pres -
sur e senso r ('9 7 - 9 8 models) .Wir
e sid e o f femal e terminal s
A (26P)
PCM CONNECTOR S
Repair ope n i n th e wire(s )
betwee n PC M (A13 , B1 ) an d
PGM-F I mai n relay .
Chec k fo r poo r connection s
o r loos e wire s a t th e PGM-F I
mai n relay .
Tes t th e PGM-F I mai n rela y
(se e pag e 11-129 ). Wir
e sid e o f femal e terminal s
PCM CONNECTOR S
A (26P)B (16P)
Repai r ope n i n th e wire(s )
betwee n PC M (A26 , B9 ) an d
G10 1 tha t ha d mor e tha n 1. 0 V .Wir e sid e o f femal e terminal s
Check fo r a n ope n i n th e wire s
(IG P lines) :
1 . Tur n th e ignitio n switc h O N (II) .
2 . Measur e voltag e betwee n bod y
groun d an d PC M connecto r
terminal s A1 3 an d B 1 individu -
ally .B (16P )
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Fuel Suppl y Syste m
Fuel Pressur e (cont'd )
Inspectio n
1 . Reliev e fue l pressur e (se e pag e 11-119 ).
2 . Remov e th e servic e bol t o n th e fue l rai l ('9 7 - 9 8
models : o n th e fue l filter ) whil e holdin g th e banj o
bol t wit h anothe r wrench . Attac h th e specia l tool .
'9 6 model :
FUEL
PRESSUR E
GAUG E
07406-004000 1
CLAMP
'97 - 9 8 models :
CLAMP
FUEL
PRESSUR E
REGULATO R
FUE L
PRESSUR E
GAUG E
07406-004000 1
FUEL FILTE R
3.
FUE L
PRESSUR E
REGULATO R
Start th e engine . Measur e th e fue l pressur e wit h th e
engin e idlin g an d th e vacuu m hos e o f th e fue l pres -
sur e regulato r disconnecte d fro m th e fue l pressur e
regulato r an d pinched . I f th e engin e wil l no t start , tur n
th e ignitio n switc h O N (II) , wai t fo r tw o seconds , tur n
i t OFF , the n bac k o n agai n an d rea d th e fue l pressure .
Pressur e shoul d be :
26 0 - 31 0 kP a (2.6 5 - 3.1 5 kgf/cm
2, 3 8 - 4 5 psi ) 4
. Reconnec t vacuu m hos e t o th e fue l pressur e regula -
tor.
Pressur e shoul d be :
19 0 - 24 0 kP a (1.9 4 - 2.4 5 kgf/cm2, 2 8 - 3 5 psi )
I f th e fue l pressur e is no t a s specified , firs t chec k th e
fue l pum p (se e pag e 11-128 ). I f th e fue l pum p is OK ,
chec k th e following :
I f th e fue l pressur e i s highe r tha n specified ,
inspec t for :
— Pinche d o r clogge d fue l retur n hos e o r line .
— Fault y fue l pressur e regulato r (se e pag e 11-124 ).
I f th e fue l pressur e i s lowe r tha n specified , inspec t
for:
— Clogge d fue l filter .
— Fault y fue l pressur e regulato r (se e pag e 11-124 ).
— Leakag e in th e fue l line .
ProCarManuals.com

Fuel Injector s
Replacemen t
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 . Reliev e fue l pressur e (se e pag e 11-119 ).
2 . Remov e th e engin e cover .
3 . Disconnec t th e connector s fro m th e fue l injectors .
4 . 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 .
5 . Disconnec t th e fue l hos e fro m th e fue l rail .
6 . Remov e th e retaine r nut s fro m th e fue l rai l an d harnes s holder .
7 . Disconnec t th e fue l rail .
8. Remov e th e fue l injector s fro m th e intak e manifold .
'96 model :
ENGINECOVER
O-RIN G
Replace .
CUSHIO NRINGReplace .
FUE L
INJECTO R
SEALRINGReplace .
HARNES S
HOLDE R
FUE L
RAIL S
PCVVALV E
12 N- m(1.2 kgf-m ,
8. 7 Ibf-ft )
22 N- m(2.2 kgf-m ,
1 6 Ibf-ft )
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