check engine ACURA TL 1995 Service Workshop Manual

Engine Oil

Inspection

1. Check engine oil level with the engine off and the car

parked on level ground.

2. Make certain that the oil level indicated on the dip-

stick is between the upper and lower marks.

3. If the level has dropped close to the lower mark, add

oil until it reaches the upper mark.

CAUTION: Insert the dipstick carefully to avoid

bending it.ProCarManuals.com

The numbers in the middle of the API Service label tell

you the oil's SAE viscosity or weight. Select the oil for

your car according to this chart:

An oil with a viscosity of 5W - 30 is preferred for

improved fuel economy and year-round protection in the

car. You may use a 10W - 30 oil if the climate in your area

is limited to the temperature range shown on the chart.

4. Fill the engine with oil up to the specified level, run

the engine for more than three minutes, then check

for oil leakage.ProCarManuals.com

Oil Pressur e
Testing
If th e oi l pressur e warnin g ligh t stay s o n wit h th e engin e
running , chec k th e engine oil level . I f th e oi l leve l i s cor -
rect :
1 . Connec t a tachometer .
2 . Remov e th e engin e oi l pressur e switch , an d instal l a n
oi l pressur e gauge .
3 . Star t th e engine . Shu t i t of f immediatel y i f th e gaug e
register s n o oi l pressure . Repai r th e proble m befor e
continuing .
4. Allo w th e engin e to reac h operatin g temperatur e (fa n
come s o n a t leas t twice) . Th e pressur e shoul d be :
Engin e Oi l Temperature : 176° F (80°C )
Engin e Oi l Pressure :
A t Idle : 6 9 kP a (0. 7 kgf/cm
2,1 0 psi )
minimu m
A t 3,00 0 rpm : 34 0 kP a (3. 5 kgf/cm
2, 5 0 psi )
minimu m
• I f oi l pressur e i s withi n specifications , replac e th e
oi l pressur e switc h an d recheck .
• I f oi l pressur e is NO T withi n specifications , inspec t
th e oi l pum p (se e pag e 8-14 ).
ADAPTE R(1/8"-28, BSPT )(Commerciall y available )
OIL PRESSUR E GAUG E(Commerciall y available )
ENGINE OI L PRESSUR E SWITC HMOUNTIN G HOL E
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System Description

Vacuum Connections (cont'd)

'95 - 96 models:

PRIMARY HEATED OXYGEN SENSOR (PRIMARY HO2S)

SECONDARY HEATED OXYGEN SENSOR (SECONDARY

HO2S)

MASS AIR FLOW (MAP) SENSOR

ENGINE COOLANT TEMPERATURE (ECT) SENSOR

INTAKE AIR TEMPERATURE (IAT) SENSOR

FRONT KNOCK SENSOR (FKS)

REAR KNOCK SENSOR (RKS)

IDLE AIR CONTROL (IAC) VALVE

FAST IDLE THERMO VALVE

IDLE ADJUSTING SCREW

THROTTLE BODY (TB)

FUEL INJECTOR

FUEL FILTER

FUEL PRESSURE REGULATOR

FUEL PULSATION DAMPER

FUEL PUMP (FP)

FUEL TANK

FUEL TANK EVAPORATIVE EMISSION (EVAP) VALVE

AIR CLEANER

RESONATOR

CRANKSHAFT SPEED FLUCTUATION (CKF) SENSOR

INTAKE AIR BYPASS (IAB) CHECK VALVE
INTAKE AIR BYPASS (IAB) VACUUM TANK

INTAKE AIR BYPASS (IAB) CONTROL SOLENOID VALVE

INTAKE AIR BYPASS (IAB) CONTROL DIAPHRAGM

EXHAUST GAS RECIRCULATION (EGR) VACUUM CONTROL

VALVE

EXHAUST GAS RECIRCULATION (EGR) CONTROL

SOLENOID VALVE

EXHAUST GAS RECIRCULATION (EGR) VALVE

EXHAUST GAS RECIRCULATION (EGR) VALVE LIFT

SENSOR

POSITIVE CRANKCASE VENTILATION (PCV) VALVE

EVAPORATIVE EMISSION (EVAP) PURGE CONTROL

SOLENOID VALVE

EVAPORATIVE EMISSION (EVAP) PURGE FLOW SWITCH

EVAPORATIVE EMISSION (EVAP) CONTROL CANISTER

EVAPORATIVE EMISSION (EVAP) PURGE CONTROL

DIAPHRAGM VALVE

EVAPORATIVE EMISSION (EVAP) TWO WAY VALVE

WARM UP THREE WAY CATALYTIC CONVERTER (WU TWC)

THREE WAY CATALYTIC CONVERTER (TWC)

WATER VALVE CONTROL SOLENOID VALVE

WATER VALVE CONTROL DIAPHRAGM

WATER VALVE CHECK VALVEProCarManuals.com

'97 - 98 models:

Vacuum hose No.

PRIMARY HEATED OXYGEN SENSOR (PRIMARY HO2S)

SECONDARY HEATED OXYGEN SENSOR (SECONDARY

HO2S)

MASS AIR FLOW (MAP) SENSOR

ENGINE COOLANT TEMPERATURE (ECT) SENSOR

INTAKE AIR TEMPERATURE (IAT) SENSOR

FRONT KNOCK SENSOR (FKS)

REAR KNOCK SENSOR (RKS)

IDLE AIR CONTROL (IAC) VALVE

FAST IDLE THERMO VALVE

IDLE ADJUSTING SCREW

THROTTLE BODY (TB)

FUEL INJECTOR

FUEL FILTER

FUEL PRESSURE REGULATOR

FUEL PULSATION DAMPER

FUEL PUMP (FP)

FUEL TANK

FUEL TANK EVAPORATIVE EMISSION (EVAP) VALVE

AIR CLEANER

RESONATOR

CRANKSHAFT SPEED FLUCTUATION (CKF) SENSOR

INTAKE AIR BYPASS (IAB) CHECK VALVE

INTAKE AIR BYPASS (IAB) VACUUM TANK

INTAKE AIR BYPASS (IAB) CONTROL SOLENOID VALVE
INTAKE AIR BYPASS (IAB) CONTROL DIAPHRAGM

EXHAUST GAS RECIRCULATION (EGR) VACUUM CONTROL

VALVE

EXHAUST GAS RECIRCULATION (EGR) CONTROL

SOLENOID VALVE

EXHAUST GAS RECIRCULATION (EGR) VALVE

EXHAUST GAS RECIRCULATION (EGR) VALVE LIFT

SENSOR

POSITIVE CRANKCASE VENTILATION (PCV) VALVE

EVAPORATIVE EMISSION (EVAP) PURGE CONTROL

SOLENOID VALVE

EVAPORATIVE EMISSION (EVAP) CONTROL CANISTER

EVAPORATIVE EMISSION (EVAP) CONTROL CANISTER

VENT SHUT VALVE

EVAPORATIVE EMISSION (EVAP) THREE WAY VALVE

EVAPORATIVE EMISSION (EVAP) TWO WAY VALVE

EVAPORATIVE EMISSION (EVAP) BYPASS SOLENOID

VALVE

FUEL TANK PRESSURE SENSOR

WARM UP THREE WAY CATALYTIC CONVERTER (WU TWC)

THREE WAY CATALYTIC CONVERTER (TWC)

WATER VALVE CONTROL SOLENOID VALVE

WATER VALVE CONTROL DIAPHRAGM

WATER VALVE CHECK VALVEProCarManuals.com

How to Read Flowcharts

A flowchart is designed to be used from start to final repair. It's like a map showing you the shortest distance. But beware:

If you go off the "map" anywhere but a "stop" symbol, you can easily get lost.

Describes the conditions or situation to start a troubleshooting flowchart.

Asks you to do something; perform a test, set up a condition etc.

Asks you about the result of an action, then sends you in the appropriate troubleshooting direction.

The end of a series of actions and decisions, describes a final repair action and sometimes directs you to

an earlier part of the flowchart to confirm your repair.

NOTE:

The term "Intermittent Failure" is used in these charts. It simply means a system may have had a failure, but it checks

out OK at this time. If the Malfunction Indicator Lamp (MIL) on the dash does not come on, check for poor connections

or loose wires at all connectors related to the circuit that you are troubleshooting (see illustration below).

Most of the troubleshooting flowcharts have you reset the Engine Control Module (ECM) and try to duplicate the

Diagnostic Trouble Code (DTC). If the problem is intermittent and you can't duplicate the code, do not continue though

the flowchart. To do so will only result in confusion and, possibly, a needlessly replaced ECM.

"Open" and "Short" are common electrical terms. An open is a break in a wire or at a connection. A short is an acci-

dental connection of a wire to ground or to another wire. In simple electronics, this usually means something won't

work at all. In complex electronics (like ECM's), this can sometimes mean something works, but not the way it's sup-

posed to.

TIGHT

LOOSEProCarManuals.com

4. A/ C Compresso r Clutc h Rela y
When th e EC M receive s a deman d fo r coolin g fro m th e ai r conditionin g system , i t delay s th e compresso r fro m bein g
energized , an d enriche s th e mixtur e to assur e smoot h transitio n to th e A/ C mode .
5 . Evaporativ e Emissio n (EVAP ) Purg e Contro l Solenoi d Valv e
Whe n th e engin e coolan t temperatur e i s belo w 167° F (75°C ) ('9 7 - 9 8 models : 158° F (70°C) , th e EC M control s th e
EVA P purg e contro l solenoi d valv e whic h cut s vacuu m to th e EVA P purg e contro l caniste r diaphragm .
6 . Intak e Ai r Bypas s (IAB ) Contro l Solenoi d Valv e
Whe n th e engin e spee d i s belo w 4,80 0 rpm , th e IA B contro l solenoi d valv e i s activate d b y a signa l fro m th e ECM ,
intak e ai r flow s throug h th e smalle r chamber , the n hig h torqu e i s delivered. At speed s highe r tha n 4,80 0 rpm , th e
solenoi d valv e i s deactivate d b y th e ECM , an d intak e ai r flow s throug h th e large r chambe r i n orde r t o reduc e th e
resistanc e in airflow .
7 . Exhaus t Ga s Recirculatio n (EGR ) Contro l Solenoi d Valv e
Whe n th e EG R is require d fo r contro l o f oxide s o f nitroge n (NOx ) emissions , th e EC M control s th e EG R contro l
solenoi d valv e whic h supplie s regulate d vacuu m to th e EG R valve .
8 . Alternato r Contro l
Th e syste m control s th e voltag e generate d a t th e alternato r i n accordanc e wit h th e electrica l loa d an d drivin g mode ,
whic h reduce s th e engin e loa d to improv e th e fue l economy .
ECM Fail-safe/Back-u p Function s
1. Fail-saf e Functio n
Whe n a n abnormalit y occur s in a signa l fro m a sensor , th e EC M ignore s tha t signa l an d assume s a pre-programme d
valu e fo r tha t senso r tha t allow s th e engin e to continu e to run .
2 . Back-u p Functio n
Whe n a n abnormalit y occur s in th e EC M itself , th e fue l injector s ar e controlle d b y a back-u p circui t independen t o f th e
syste m in orde r t o permi t minima l driving .
3 . Self-diagnosi s Functio n [Malfunctio n Indicato r Lam p (MIL) ]
Whe n a n abnormalit y occur s i n a signa l fro m a sensor , th e EC M supplie s groun d fo r th e MI L an d store s th e DT C in
erasable memory . Whe n th e ignitio n i s initiall y turne d on , th e EC M supplie s ground for th e MI L fo r tw o second s t o
chec k th e MI L bul b condition .
4 . Tw o Tri p Detectio n Metho d ('9 5 - 9 6 models )
T o preven t fals e indications , th e Tw o Tri p Detectio n Metho d is use d fo r th e MA F sensor , H02S , fue l metering-related ,
idl e contro l system , EC T sensor , an d EG R syste m self-diagnosti c functions . Whe n a n abnormalit y occurs , th e EC M
store s i t i n it s memory . Whe n th e sam e abnormalit y recur s afte r th e ignitio n switc h i s turne d OF F an d O N (II ) again ,
th e EC M inform s th e drive r b y lightin g th e MIL .
However ,
to eas e troubleshooting , thi s functio n is cancelle d when you shor t the servic e check connector . The MI L will
the n blin k immediatel y whe n a n abnormalit y occurs .
5 . Tw o (o r Three ) Drivin g Cycl e Detectio n Metho d ('9 5 - 9 6 models )
A "Drivin g Cycle " consist s o f startin g th e engine , beginnin g close d loo p operation , an d stoppin g th e engine . I f misfir -
in g tha t increase s emission s o r EVA P contro l syste m malfunctio n i s detecte d i n tw o consecutiv e drivin g cycles , o r
TW C deterioratio n is detecte d in thre e consecutiv e drivin g cycles , th e EC M turn s th e MI L on .
However , t o eas e troubleshooting , thi s functio n is cancelle d whe n yo u shor t th e servic e chec k connector . Th e MI L wil l
the n blin k immediatel y whe n a n abnormalit y occurs .
6 . Tw o Drivin g Cycl e Detectio n Metho d ('9 7 - 9 8 models )
T o preven t fals e indications , th e "tw o drivin g cycl e detectio n method " i s use d fo r th e H02S , fue l metering-related ,
idl e contro l system , EC T sensor , EG R system , TW C an d EVA P contro l syste m an d othe r self-diagnosti c functions .
Whe n a n abnormalit y occurs , th e EC M store s i t i n it s memory . Whe n th e sam e abnormalit y recur s afte r switc h i s
turne d OF F an d O N (II ) again , th e EC M inform s th e drive r b y turnin g o n th e MIL .
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PGM-FI System

Engine Control Module (ECM)

Is the low oil pressure light on?

Try to start the engine.

Does the engine start?

Check for an open in the wire or

bulb (MIL line):

1. Turn the ignition switch OFF.

2. Connect the ECM connector ter-

minal A7 to body ground with a

jumper wire.

3. Turn the ignition switch ON (II).
NOTE: If this symptom is intermittent, check for a loose fuse No. 1 (BACK UP

LIGHTS, METER LIGHTS, 10 A) in the under-dash fuse/relay box, a poor con-

nection at ECM terminal A7, or an intermittent open in the GRN/RED wire

between the ECM (A7) and the gauge assembly.

Is the MIL on?

Substitute a known-good ECM

and recheck. If symptom/indica-

tion goes away, replace the origi-

nal
ECM.
— Repair short in the wire

between NO. 1 (BACK-UP

LIGHTS, METER LIGHTS) (10

A) fuse and gauge assembly.

— Replace No. 1 (BACK-UP

LIGHTS, METER LIGHTS) (10 A)

fuse.

Check for an open in the wires

(PG1, PG2 lines):

1. Turn the ignition switch ON (II).

2. Measure voltage between

body ground and ECM con-

nector terminals A12 and A25

individually.

Is there less than 1.0 V?

Repair open in the wires

between ECM (A7) and gauge

assembly.

Replace the MIL bulb.
ECM CONNECTOR A (26P)

Wire side of female terminals

Repair open in the wire(s)

between ECM and G101 (located

at left side of engine) that had

more than 1.0 V.

ECM CONNECTOR A (26P)

Wire side of female terminals
The Malfunction Indicator Lamp

(MIL) never comes on (even for

two seconds) after ignition is

turned on.

Turn the ignition switch ON (II).

JUMPER WIREProCarManuals.com

PGM-FI Syste m
Engine Contro l Modul e (ECM ) (cont'd )
(From pag e 11-53 )
Chec k fo r a shor t i n th e wir e (MI L
line) :1. Tur n th e ignitio n switc h OFF .2. Disconnec t th e EC M connec -
to r A (26P) .
3. Tur n th e ignitio n switc h O N (II) .
Is th e MI L ON ?Repai r shor t t o bod y groun d i n
th e wir e betwee n th e EC M (A7 )
and MIL .
Substitut e a known-goo d EC M
an d recheck . I f symptom/indica -
tio n goe s away , replac e th e origi -
nal ECM .
(From pag e 11-53 )
I s th e fus e OK ? Repai
r shor t i n th e wir e
betwee n EC U (ECM ) (1 5 A )
fus e an d PGM-F I mai n relay .
Replac e EC U (ECM ) (1 5 A ) fuse .
Inspec t No . 2 FUE L PUM P (1 5 A )
fus e i n th e under-das h fuse/rela y
box.
Is th e fus e OK ? Repai
r shor t i n th e wir e
betwee n No . 2 FUE L PUM P
(1 5 A ) fus e an d PGM-F I mai nrelay .Replac e No . 2 FUE L PUM P(15A) fuse.
Chec k fo r a shor t i n a sensor :
1. Tur n th e ignitio n switc h ON .2. Disconnec t th e 3 P connecto r
o f eac h senso r on e a t time :
• T P senso r
• EG R valv e lif t senso r
• Fue l tan k pressur e senso r
('97-98 models )
(To pag e 11-55 )
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(From pag e 11-108 )
I s ther e a clickin g nois e fro m
th e A/ C compresso r clutch ?
Chec k th e A/ C operation :
1 . Star t th e engine .
2 . Tur n th e blowe r switc h ON .
3 . Tur n th e A/ C switc h ON .
Doe s th e A/ C operate ?
Ai r conditionin g signa l i s OK . Chec
k fo r a n ope n i n th e wire
(AC C line) :Momentaril y connec t th e A/ C
clutc h rela y connecto r termina l
No. 2 to bod y groun d wit h ajumpe r wir e severa l times . A/
C CLUTC H RELA Y CONNECTO R (C328 )JUMPE RWIRE
Wire sid e o f
femal e terminal s
I s ther e a clickin g nois e fro m
th e A/ C compresso r clutch ? Se
e ai r conditione r inspectio n
(se e sectio n 22 ).
Repai r ope n i n th e wir e betwee n
th e EC M (A8 ) an d th e A/ C clutc h
relay.
ECM CONNECTOR S
A (26P)B (16P)
Chec k fo r a n ope n i n th e wir e
(AC C line) :
Measur e voltag e betwee n EC M
connecto r terminal s A2 6 an d B3 . Wir
e sid e o f femal e terminal s
I s voltag e les s tha n 1. 0 V ? Repai
r ope n i n th e wir e betwee n
th e EC M (B3 ) an d th e A/ C switch .
Substitut e a known-goo d EC M
an d recheck . I f symptom/indi -
catio n goe s away , replac e th e
origina l ECM .
Se e th e ai r conditione r inspec -
tion (se e sectio n 22 ).
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