Vss ACURA TL 1995 Service Repair Manual

41. Disconnect the vehicle speed sensor (VSS) connec-

tor, then remove the VSS/power steering speed

sensor.

Do not disconnect the fluid hoses.

6 x 1.0 mm

12 N-m (1.2 kgf-m,

8.7 Ibf-ft)
VSS CONNECTOR

VSS/POWER STEERING

SPEED SENSOR

42. Remove the heat shields from exhaust pipe A.

HEAT

SHIELDS
6 x 1.0 mm

12 N-m (1.2 kgf-m,

8.7 Ibf-ft)
43. Remove exhaust pipe A.

EXHAUST

PIPE A

GASKET

Replace.
SELF-LOCKING NUT

8 x
1.25
mm

22 N-m (2.2 kgf-m, 16 Ibf-ft)

Replace.

GASKETS

Replace.

GASKET

Replace.

TWC
6 x 1.0 mm

9.8 N-m (1.0 kgf-m,

7.2 Ibf-ft)
SELF-LOCKING NUT

8 x
1.25
mm

22 N-m (2.2 kgf-m,

16 Ibf-ft)

Replace.
SELF-LOCKING NUTS

10 x
1.25
mm

54 N-m (5.5 kgf-m,

40 Ibf-ft)

Replace.

44. Remove the wire harness cover and grommet, then

remove the three way catalytic converter (TWC).

SELF-LOCKING NUT

10 x
1.25
mm

32 N-m (3.3 kgf-m,

24 Ibf-ft)

Replace.
GROMMET

WIRE HARNESS

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Component Location s
Index
EVAPORATIV E EMISSIO N(EVAP)PURGE CONTRO L
SOLENOI D VALV E ('9 7 - 9 8 models )
RIGH T KNOC K SENSO R (BAN K 1 )
EXHAUS T GA S RECIRCULATIO N (EGR )
VALV E an d LIF T SENSO R
RIGH T PRIMAR Y HEATE D
OXYGE N SENSO R (RIGH T
PRIMAR Y HO2S )
(BAN K 1 SENSO R 1 )
SPAR K PLU G VOLTAG E
DETECTIO N MODUL E /
IGNITIO NCONTRO LMODULE(ICM)Troubleshooting ,Section 2 3
LEF T KNOC K SENSO R (BAN K 2 )
SPAR K PLU G VOLTAG E SENSO R
(buil t int o th e IGNITIO N COI L
Assembly )
LEF T PRIMAR Y HEATE D
OXYGE N SENSO R
(LEF T PRIMAR Y HO2S )
(BAN K 2 SENSO R 1 )
FUE L TAN K PRESSUR E
SENSO R ('9 7 - 9 8 models )
EVAPORATIV E EMISSIO N
(EVAP ) BYPAS S SOLENOI D
VALV E ('9 7 - 9 8 models )
Replacement , pag e 11-16 9
EVAPORATIV E EMISSIO N
(EVAP ) TW O WA Y VALV E
('9 7 - 9 8 models )
Replacement , pag e 11-16 9
INTAK E
AIRBYPAS S (IAB )LOWCONTRO L
SOLENOI D
VALV E
Troubleshooting ,page 11-139
INTAK E AI R BYPAS S (IAB ) HIG H
CONTRO L SOLENOI D VALV E
Troubleshooting , pag e 11-139
POWE R STEERIN G PRESSUR E
(PSP ) SWITC H
Troubleshooting , pag e 11-11 0
ENGIN E COOLAN T TEMPERATUR E (ECT ) SENSO R
THROTTL E
POSITIO N (TP )
SENSO R EVAPORATIV
E EMISSIO N (EVAP )
PURG E FLO W SWITC H ('9 6 mode l only )
EVAPORATIV E EMISSIO N
(EVAP)PURGE CONTRO L
SOLENOI D VALV E ('9 6 mode l only )
CRANKSHAF T POSITION /
CYLINDE R POSITIO N
(CKP/CYP ) SENSO R
INTAK E AI R TEMPERATUR E (IAT ) SENSO R
IDL E AI R CONTRO L (IAC ) VALV E
VEHICL
E SPEE D
SENSO R (VSS )
CONTRO
L BO X
pag e 11- 9
For Troubleshooting of DTC related components, see chart on page 11-45.
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Powertrain Contro l Modul e Dat a
B y connectin g th e OB D II sca n too l o r th e Hond a PG M Teste r t o th e 16 P dat a lin k connecto r (DLC) , variou s dat a ca n b e
retrieve d fro m th e PCM . Th e item s liste d in th e tabl e belo w confor m to th e SA E recommende d practice .
Th e Hond a PG M Teste r als o read s dat a beyon d tha t recommende d b y SAE .
Understandin g thi s dat a wil l hel p t o fin d th e cause s o f intermitten t failure s o r engin e problems .
NOTE:
The "operatin g values " give n belo w ar e approximat e value s an d ma y b e differen t dependin g o n th e environmen t an d
the individua l car .
Unles s note d otherwise , "a t idl e speed " mean s idlin g wit h th e engine completel y warme d up , transmissio n i n o r
position , an d th e A/ C an d al l accessorie s turne d off .
Dat aDescriptio nOperating Valu e
Freeze Dat a
Diagnosti c
Troubl e Cod e
(DTC )
If th e PC M detect s a problem , i t wil l stor e it a s a cod e
consistin g o f on e lette r an d fou r numbers .
Dependin g o n th e problem , a n SAE-define d cod e
(P0xxx ) o r a Honda-define d cod e (P1xxx ) wil l b e outpu t
t o th e tester . I
f n o proble m is detected ,
ther e i s n o output .
Engin e Spee d Th
e PC M compute s engin e spee d fro m th e signal s sen t
fro m th e Crankshaf t Positio n sensor .
Thi s dat a is use d fo r determinin g th e tim e an d amoun t
o f fue l injection . Nearl
y th e sam e a s
tachomete r indicatio n a t
idl e speed :
640 5 0 rp m
Vehicl e Spee d Th
e PC M convert s puls e signal s fro m th e Vehicl e
Spee d Senso r (VSS ) int o spee d data . Nearl
y th e sam e a s
speedomete r indicatio n
Manifol d
Absolut e
Pressur e (MAP )
The absolut e pressur e create d in th e intak e manifol d b y
engin e loa d an d speed . Wit
h engin e stopped :
Nearl y th e sam e a s atmo -
spheri c pressur e a t idl e
speed :
24-37 kP a (180-28 0
mmHg, 7.1-11. 0 inHg )
Engin e Coolan t
Temperatur e
(ECT)
The EC T senso r convert s coolan t temperatur e int o
voltag e an d signal s th e PCM . Th e senso r i s a thermisto r
whos e interna l resistanc e change s wit h coolan t
temperature . Th e PC M use s th e voltag e signal s fro m
th e EC T senso r t o determin e th e amoun t o f injecte d
fuel . Wit
h col d engine :
Sam e a s ambien t temper -
atur e an d IA T
Wit h engin e warme d up :
approx . 158-212° F
(70-100°C )
Heate d Oxyge n
Senso r (H02S )
(Bank 1, Sensor 1)
(Ban k 2 , Senso r 1 )
(Senso r 2 )
Th e Heate d Oxyge n Senso r detect s th e oxyge n conten t
i n th e exhaus t ga s an d send s voltag e signal s to th e
PCM . Base d o n thes e signals , th e PC M control s th e
air/fue l ratio . Whe n th e oxyge n conten t i s hig h (tha t is ,
whe n th e rati o is leane r tha n th e stoichiometri c ratio) ,
th e voltag e signa l i s lower . Whe n th e oxyge n conten t i s
lo w (tha t is , whe n th e rati o is riche r tha n th e stoichio -
metric ratio) , th e voltag e signa l i s higher .
0.0-1.2 5 V
A t idl e speed :
about 0.1-0. 9 V
O
(Senso r 1 )
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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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A/T Contro l Syste m
The PC M termina l voltag e an d measurin g condition s ar e show n fo r th e connecto r terminal s tha t ar e relate d t o th e A/ T con -
tro l system . Th e othe r PC M termina l voltag e an d measurin g condition s ar e describe d i n sectio n 11.
PC M CONNECTO R A (26P )
Termina l Numbe r
A1 to A11
A12
A13
A14 to A24
A2 5
A2 6
Signa l Descriptio n Measurin g Conditions/Termina l Voltag e
-see section 11 -
PG1
IGP 1
Groun d
Power suppl y syste m With ignitio n switc h O N (II) : Batter y
With ignitio n switc h OFF : 0 V
voltag e
- see section 11 -
PG2
LG1
Groun d
Groun d
PC M CONNECTO R B (16P )
Termina l Numbe r
B1
B 2 to B 8
B9
B10 to B12
B1 3
B14 to B16
Signa l
IGP2
Descriptio n
Power suppl y syste m
Measurin g Conditions/Termina l Voltag e
With ignitio n switc h O N (II) : Batter y voltag e
Wit h ignitio n switc h OFF : 0 V
- se e sectio n 1 1 -
LG 2Groun d
- se e sectio n 1 1 -
VS SVehicl e Spee d Senso r (VSS )
signa l Inpu tWith ignitio n switc h O N (II ) an d rotatin g fron t
wheels : 0V - 5V cycle
- see section 11 -
PCM CONNECTO R C (12P )
Termina l Numbe r
C1 t o C 4
C5
C6 to C12
Signa lDescriptio nMeasuring Conditions/Termina l Voltag e
-see sectio n 1 1 -
SC SServic e chec k signa l
With ignitio n switc h O N (II ) an d servic e chec k
connecto r open : 5 V
Wit h ignitio n switc h O N (II ) an d servic e chec k
connecto r connecte d wit h specia l tool : 0 V
- see section 11 -
PCM Termina l Voltage/Measurin g Condition s
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Component Locations

POWERTRAIN CONTROL

MODULE (PCM)

PGM-FI

MAIN RELAY

COUNTERSHAFT

SPEED SENSOR
MAINSHAFT SPEED SENSOR

LOCK-UP CONTROL

SOLENOID VALVE

A/B ASSEMBLY
SHIFT CONTROL SOLENOID

VALVE A/B

(Located in transmission.)

VEHICLE SPEED

SENSOR(VSS)
LINEAR SOLENOID

(Located in transmission.)
AUTOMATIC TRANSAXLE (A/T)

GEAR POSITION SWITCHProCarManuals.com

Symptom-to-Component Char t
Electrica l Syste m
Diagnosti c
Troubl e Cod e
(DTC) *
P1753
(1)
P175 8
(2)
P179 1
(4)
P170 5
(5)
P170 6
(6)
P075 3
(7)
P075 8
(8)
P072 0
(9)
P071 5
(15)
P176 8
(16)
Indicato r
Light
Blink s
Blink s
Blinks
Blink s
OFF
Blink s
Blink s
Blinks
'96, '97
model s
OFF
'98 mode l
Blinks
Blink s
Sympto m
• Lock-u p clutc h doe s no t engage .
• Lock-u p clutc h doe s no t disen -
gage.
• Lock-u p clutc h doe s no t engage .
• Lock-u p clutc h doe s no t engage .
• Fail s t o shif t othe r tha n 2n d - 4t h
gears .
• Lock-u p clutc h doe s no t engage .
• Fail s t o shif t othe r tha n 2n d - 3r d
- 4t h gears .
• Lock-u p clutc h doe s no t engage .
• Fail s to shif t (betwee n 1s t - 4t h o r
2n d - 3r d gea r only) .
• Fail s t o shif t (stuc k in 4t h gear) .
• Fail s t o shif t (stuc k i n 1s t o r 4t h
gears) .
• Lock-u p clutc h doe s no t engage .
• Transmissio n jerk s har d whe n
shifting .
• Lock-u p clutc h dos e no t engage .
• Transmissio n jerk s har d whe n
shifting .
• Lock-u p clutc h doe s no t engage .
• Fail s t o shif t (stuc k in 4t h gear) . Possibl
e Caus e
• Disconnecte d lock-u p contro l solenoi d
valv e A connecto r
• Shor t o r ope n i n lock-u p contro l
solenoi d valv e A wir e
• Fault y lock-u p contro l solenoi d valv e A
• Ope n in V B SO L lin e
• Disconnecte d lock-u p contro l solenoi d
valv e B connecto r
• Shor t o r ope n in lock-u p contro l
solenoi d valv e B wir e
• Fault y lock-u p contro l solenoi d valv e B
• Ope n in V B SO L lin e
• Disconnecte d vehicl e spee d senso r
(VSS) connecto r
• Shor t o r ope n in VS S wir e
• Fault y VS S
• Shor t i n A/ T gea r positio n switc h wir e
• Fault y A/ T gea r positio n switc h
• Disconnecte d A/ T gea r positio n switc h
connecto r
• Ope n in A/ T gea r positio n switc h wir e
• Fault y A/ T gea r positio n switc h
• Disconnecte d shif t contro l solenoi d
valv e A connecto r
• Shor t o r ope n i n shif t contro l solenoi d
valv e A wir e
• Fault y shif t contro l solenoi d valv e A
• Ope n in V B SO L lin e
• Disconnecte d shif t contro l solenoi d
valv e B connecto r
• Shor t o r ope n i n shif t contro l solenoi d
valv e B wir e
• Fault y shif t contro l solenoi d valv e B
• Ope n in V B SOL line
• Disconnecte d countershaf t spee d sen -
sor connecto r
• Shor t o r ope n i n countershaf t spee d
senso r wir e
• Fault y countershaf t spee d senso r
• Disconnecte d mainshaf t spee d senso r
connecto r
• Shor t o r ope n i n mainshaf t spee d sen -
so r wir e
• Fault y mainshaf t spee d senso r
• Disconnecte d linea r solenoi d connecto r
• Shor t o r ope n i n linea r solenoi d wir e
• Fault y linea r solenoi d
• Ope n in V B SOL line Refe
r t o
Pag e
14-7 0
14-72
14-74
14-7 5
14-78
14-8 0
14-82
14-84
14-8 6
14-8 8
(DTC)* : Th e DTC s in parenthese s ar e th e code s o f th e indicato r ligh t indicate s whe n th e servic e chec k connecto r i s con -
necte d to th e specia l too l (SC S servic e connector) .
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Differential Assembl y
Removal (cont'd )
6. Remov e th e righ t fron t bea m bridge .
RIGHT FRON T BEA M BRIDG E
7. Disconnec t th e vehicl e spee d senso r (VSS ) con -
necter , the n remov e th e VSS/powe r steerin g spee d
sensor .
NOTE: D o rio t disconnec t th e hoses .
VSS CONNECTE R
VSS/POWE R STEERIN G
SPEE D SENSO R
8. Remov e th e mountin g bolt s an d 2 6 m m shim , the n
remov e th e differentia l assembly .
O-RINGReplace .
DIFFERENTIA LASSEMBLY
26 m m SHI M
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Differential Assembl y
Installatio n (cont'd )
8. Instal l th e vehicl e spee d senso r (VSS)/powe r steer -
in g spee d sensor , the n connec t th e VS S connecter .
VSS CONNECTE R
6 x 1. 0 m m12 N- m (1. 2 kgf-m , 8. 7 Ibf-ft )
VSS/POWE R STEERIN G
SPEE D SENSO R
9. Instal l th e righ t fron t bea m bridge .
10 x 1.2 5 mm38 N- m (3. 9 kgf-m , 2 8 Ibf-ft )
RIGH T FRON T BEA M BRIDG E
10. Remov e th e steerin g gearbo x mountin g bolts , the n
instal l th e lowe r plat e an d th e steerin g gearbo x
mounting bolts .
STEERIN G GEARBO XMOUNTING BOLT S59 N- m (6. 0 kgf-m ,
4 3 Ibf-ft )
10 x 1.2 5 mm38 N- m (3. 9 kgf-m ,28 Ibf-ft )
11. Instal l th e splas h shiel d
SPLAS HSHIELD •
LOWE R
PLATE
6 x 1. 0 m m9.8 N- m (1. 0 kgf-m ,
7. 2 Ibf-ft )
12. Instal l th e driveshaft s an d th e intermediat e shaf t
(se e sectio n 16 ).
13 . Refil l th e differentia l wit h oi l (se e pag e 15-4 ).
14 . Chec k th e fron t whee l alignmen t (se e sectio n 18 ).
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Gauge Assembl y
Componen t Locatio n Inde x
VEHICL E SPEE D SENSO R (VSS )
Replacement , pag e 23-9 8
GAUGE ASSEMBL Y
Bul b Locations , pag e 23-9 5
ENGIN E COOLAN T TEMPERATUR E
(ECT) GAUG E SENDIN G UNI TTest , pag e 23-9 9
ENGIN E OI L PRESSUR E SWITC H
Test , pag e 23-9 8
NOTE : Refer to page 23-110 of the '95-98 Acura 2.5TL
Servic e Manual , P/ N 61SW504 , for the items not shown in
thi s sub-section .
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