ACURA NSX 1991 Service Repair Manual

Inspection


Replacement
1. Remove the timing belt (see page 6-15) ('91-'93) or

('94-'96).

2. Check that the water pump pulley turns counterclock-

wise.

3. Check for signs of seal leakage.
NOTE: A small amount of "weeping" from the bleed
hole is normal.

Turns
counterclockwise

BLEED HOLE
BLEED HOLE

1. Remove the timing belt (see page 6-15 ('91-'93) or
('94-'96).

2. Unscrew the bolts, then remove the water pump.
NOTE: Inspect and clean the 0-ring groove and
mating surface with the cylinder block.

DOWEL PIN
SPECIAL BOLTS
6 x 1.0 mm: 7 BOLTS
12 N·m

(1 .2 kg-m, 9 Ib-ft)

Replace,

WATER PUMP
0-RING

Replace.
SPECIAL BOLTS
8 x 1.25 mm: 2 BOLTS

22 N·m
(2.2 kg-m,
16 Ib-ft)
Replace.

3. Install the water pump in the reverse order of
removal.

NOTE:
Keep the 0-ring in position when installing.
Clean up spilled engine coolant.ProCarManuals.com

Special Tool s
11-151,11-155, 11-163,
11-164, 11-168, 11-169,
11-170, 11-171, 11-173
11-173
11-38
11-40
11-133, 11-137
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Component Location s
Index
EXHAUS T GA S RECIRCULATIO N (EGR ) VALV E
an d LIF T SENSO R
THROTTL E POSITIO N (TP ) SENSO R
EVAPORATIV E EMISSIO N (EVAP )
PURG E FLO W SWITC H ENGIN
E COOLAN T TEMPERATUR E (ECT ) SENSO R
INTAK E AI R TEMPERATUR E (IAT ) SENSO R
CRANKSHAF T POSITION /
CYLINDE R POSITIO N
(CKP/CYP ) SENSO R
FUE L PUM P RESISTE R
Troubleshooting , pag e 11-14 1
FUE L
INJECTO R
RESISTE RTesting,page 11-13 6
THROTTL E VALV E
CONTRO L MOTO R
CONTRO L BO X
page , 11- 8
NEUTRA L SWITC H (M/ T only )
Troubleshooting , pag e 11-12 3
FRON T KNOC K SENSO R (KS2 )
REAR KNOC K SENSO R (KS1 )
SPAR K PLU G VOLTAG E
DETECTIO N MODUL E
FRON T PRIMAR Y HEATE D
OXYGE N SENSO R (HO2S )
(BAN K 2 , SENSO R 1 )
SPAR K PLU G VOLTAG E SENSO R
(buil t int o th e IGNITIO N COI L
Assy. )
FRONT SECONDAR Y HEATE D OXYGE N
SENSO R (HO2S ) (BAN K 2 , SENSO R 2 )
REA R PRIMAR Y HEATE DOXYGEN SENSO R (HO2S )
(BAN K 1 , SENSO R 1 )
REAR SECONDARY HEATED OXYGEN SENSOR
(HO2S ) (BAN K 1, SENSO R 2)
For Troubleshooting of DTC related components. see chart on page 11-52.
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Component Location s
Index
CLUTC H SWITC H (M/ T only )
Troubleshooting , pag e 11-12 4
ACCELERATOR POSITIO N (AP )
SENSO R
THROTTL E CABL EInspection/Adjustment , pag e 11-15 0
Installation , pag e 11-15 0
PGM-F I
MAI N RELA Y
Rela y Testing , pag e 11-14 3
Troubleshooting , pag e 11-14 4
THROTTLE VALVECONTROL MOTOR RELAY
Troubleshooting , pag e 11-11 2
ENGIN E CONTRO L MODUL E (ECM )
Self-diagnosti c Procedures , pag e 11-3 8
Troubleshooting , pag e 11-6 1, and 11-62 SERVIC
E CHEC K CONNECTO R (2P )
Self-diagnosti c Procedures , pag e 11-3 8
DAT A LIN K CONNECTO R (16P )
Self-diagnosti c Procedures , pag e 11-3 8
For Troubleshooting of DTC related components, see chart on page 11-52.
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FUEL TAN K EVAPORATIV E EMISSIO N(EVAP) VALV E
EVAPORATIV E EMISSIO N(EVAP) TW O WA Y VALV ETesting , pag e 11-17 3
FUEL FIL L CA P
EVAPORATIV E EMISSIO N(EVAP) CONTRO L CANISTE R FUE
L PUM P
Testing , pag e 11-14 2
Replacement , pag e 11-14 2
FUEL FEE D PIP E
FUE L FILTE R
Replacement , pag e 11-13 8
FUEL PRESSUR E REGULATO R
Testing , pag e 11-13 7
Replacement , pag e 11-13 8
FUEL RETUR N PIP E
FUE L
VAPO R HOS E FUE
L INJECTOR S
Replacement , pag e 11-13 4
FUE L RAI L
FUE L TAN K
Replacement , pag e 11-14 7
FUE L PUM P RELA Y
Troubleshooting , pag e 11-13 9
For Troubleshooting of DTC related components, see chart on page 11-52.
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Component Location s
Index
AIR CLEANE R (ACL )
Disassembly , pag e 11-14 9 THROTTL
E BOD Y (TB )
Inspection , pag e 11-15 1
Disassembly , pag e 11-15 2
POSITIVE CRANKCAS E VENTILATIO N (PCV ) VALV E
Inspection , pag e 11-16 6
INTAK E AI R DUC T
INTAK E AI R BYPAS S (IAB ) CONTRO L DIAPHRAG M
Troubleshooting , pag e 11-15 5
Test , pag e 11-15 7 INTAK
E AI R BYPAS S (IAB ) VALV E BOD Y ASSEMBL Y
For Troubleshooting of DTC related components, see chart on page 11-52.
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System Descriptio n
Vacuum Connection s
CONTROLBOXpag e 11- 8EVA P PURG E FLO W
SWITC H
INTAKEAIRBYPAS S(IAB)DIAPHRAG M
FUEL PRESSUR E
REGULATO R EVA
P
PURG E CONTRO L
DIAPHRAG M VALV E
EVA P CONTRO L
CANISTE R
FRON T O F
VEHICL E
EG
R VALV E
LIF T SENSO RT
o EVA P TWO-WA Y
VALVE
EGR VALV E
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System Descriptio n
Vacuum Connection s (cont'd )
Control Bo x
EVAPORATIV E EMISSIO N
(EVAP ) PURG E CONTRO L SOLENOI D VALVE
EXHAUS T GA S RECIRCULATIO N
(EGR ) CONTRO L SOLENOI D VALVE EXHAUS
T GA S RECIRCULATIO N (EGR )
VACUU M CONTRO L VALV E
MANIFOL D ABSOLUT E
PRESSUR E (MAP ) SENSO R
INTAK E AI R BYPAS S
(IAB ) CONTRO L SOLENOI D
VALVETroubleshooting ,
pag e 11-15 5
INTAK E AI R BYPAS S (IAB ) CHEC K VALV E
INTAKE AI R BYPAS S (IAB ) VACUU M TAN K
For Troubleshooting of DTC related components, see chart on page 11-52.
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Vacuum hos e No .
FRON T PRIMAR Y HEATE D OXYGE N SENSO R (HO2S )
(BAN K 2 , SENSO R 1 )
REA R PRIMAR Y HEATE D OXYGE N SENSO R (HO2S )
(BAN K 1 , SENSO R 1 )
FRON T SECONDAR Y HEATE D OXYGE N SENSO R (HO2S )
(BAN K 2 , SENSO R 2 )
REA R SECONDAR Y HEATE D OXYGE N SENSO R (HO2S )(BANK 1. SENSO R 2)MANIFOL D ABSOLUT E PRESSUR E (MAP ) SENSO R
ENGIN E COOLAN T TEMPERATUR E (ECT ) SENSO R
INTAK E AI R TEMPERATUR E (IAT ) SENSO R
FRON T KNOC K SENSO R (KS2 )
REA R KNOC K SENSO R (KS1 )
AI R CLEANE R (ACL )
FUE L INJECTO R
FUE L PRESSUR E REGULATO R
FUE L FILTE R
FUE L PUM P (FP )
FUEL TAN KFUEL TAN K EVAPORATIV E EMISSIO N (EVAP ) VALV E
INTAK E AI R BYPAS S (IAB ) CHEC K VALV E INTAK
E AI R BYPAS S (IAB ) VACUU M TAN K
INTAK E AI R BYPAS S (IAB ) CONTRO L SOLENOI D VALV E
INTAK E AI R BYPAS S (IAB ) CONTRO L DIAPHRAG M
FRON T THRE E WA Y CATALYTI C CONVERTE R (TWC )
REA R THRE E WA Y CATALYTI C CONVERTE R (TWC )
POSITIV E CRANKCAS E VENTILATIO N (PCV ) VALV E
EXHAUS T GA S RECIRCULATIO N (EGR ) VALV E
EXHAUS T GA S RECIRCULATIO N (EGR ) VALV E LIF T SEN -
SOREXHAUS T GA S RECIRCULATIO N (EGR ) VACUU M CONTRO LVALVEEXHAUS T GA S RECIRCULATIO N (EGR ) CONTRO L
SOLENOI D VALV E
EVAPORATIV E EMISSIO N (EVAP ) CONTRO L CANISTE R
EVAPORATIV E EMISSIO N (EVAP ) PURG E CONTRO L
SOLENOI D VALV E
EVAPORATIV E EMISSIO N (EVAP ) PURG E CONTRO L
DIAPHRAG M VALV E
EVAPORATIV E EMISSIO N (EVAP ) PURG E FLO W SWITC H
EVAPORATIV E EMISSIO N (EVAP ) TW O WA Y VALV E
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System Descriptions

Electrical ConnectionsProCarManuals.com