ACURA NSX 1997 Service Repair Manual

13. To prevent damage to the O-rings, install the fuel injectors in the fuel rail first, then install them in the intake mani-

fold.

FUEL

RAILS

FUEL RAIL

INSULATOR

FUEL RAIL
14. Align the center line on the connector with the mark on the fuel rail.

15. Install and tighten the retainer nuts.

16. Connect the fuel hose to the fuel rail.

17. Connect the vacuum hose and fuel return hose to the fuel pressure regulator.

18. Install the connectors on the fuel injectors and the IAT sensor.

19. Install the intake manifold covers.

20. Turn the ignition switch ON (II), but do not operate the starter. After the fuel pump runs for approximately two seconds,

the fuel pressure in the fuel line rises. Repeat this two or three times, then check whether there is any fuel leakage.
MARKINGSProCarManuals.com

Fuel Supply System

Fuel Injector Resistor (A/T)

Description

The fuel injector resistor lowers the current supplied to

the fuel injectors to prevent damage to the fuel injector

coils. This allows a faster response time of the fuel injec-

tors.
Testing

1. Disconnect the fuel injector resistor connector.

2. Check for resistance between each of the fuel injec-

tor resistor terminals (2, 3, 4, 6, 7 and 8) and the

power terminal (5).

Terminal side of male terminals

Replace the fuel injector resistor with a new one if

any of the resistances are outside of the specifica-

tion.ProCarManuals.com

Fuel Pressur e Regulato r
Descriptio n
Th e fue l pressur e regulato r maintain s a constan t fue l
pressur e t o th e fue l injectors . Whe n th e differenc e
betwee n th e fue l pressur e an d manifol d pressur e
exceed s 34 3 kP a (3. 5 kgf/cm
2, 5 0 psi) , th e diaphrag m is
pushe d upward , an d th e exces s fue l i s fe d bac k int o th e
fue l tan k throug h th e fue l retur n pipe .
CLOSE D
INTAKE MANIFOL DVACUUM
DIAPHRAG M
FUEL
INLE T
OPEN
INTAK E MANIFOL DVACUUM
DIAPHRAG M
FUEL
INLE T
FUE L
RETUR N
FUEL PRESSUR EREGULATO R
2. Reconnec t th e vacuu m hos e t o th e fue l pressur e
regulator .
3 . Chec k tha t th e fue l pressur e rise s whe n th e vacuu m
hos e fro m th e fue l pressur e regulato r i s disconnecte d
again.
If th e fue l pressur e di d no t rise , replac e th e fue l
pressur e regulator .
(cont'd)
1. Attac h th e specia l too l t o th e servic e por t o f th e fue l
filte r (se e pag e 11-133 ).
Pressur e shoul d be :
32 4 - 36 3 kp a (3. 3 - 3. 7 kgf/cm
2, 4 7 - 5 3 psi )
(wit h th e fue l pressur e regulato r vacuu m hos e dis -
connecte d an d pinched )
Testin
g
Do no t smok e durin g th e test . Kee p ope n
flame s awa y fro m you r wor k area .
CLAM P
FUELPRESSUR E
GAUG E
07406 - 0040001
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Fuel Suppl y Syste m
Fuel Pressur e Regulato r (cont'd )
Replacemen t
Do no t smok e whil e workin g o n fue l sys -
tem . Kee p ope n flam e awa y fro m you r wor k area .
1 . Plac e a sho p towe l unde r fue l pressur e regulator ,
the n reliev e fue l pressur e (se e pag e 11-132 ).
2 . Disconnec t th e vacuu m hos e an d fue l retur n hose .
3 . Remov e th e tw o 6 m m retaine r bolts .
4 . Instal l th e fue l pressur e regulato r i n th e revers e
orde r o f removal , an d not e thes e items :
• Replac e th e O-ring .
• Appl y clea n engin e oi l t o th e O-rin g an d assem -
bl e i t int o it s prope r position , takin g car e no t t o
damag e th e O-ring .
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Fuel Suppl y Syste m
Fuel Filte r
Replacemen t
Do no t smok e whil e workin g o n fue l sys -
tem . Kee p ope n flam e awa y fro m you r wor k area .
Th e fue l filte r shoul d b e replace d ever y 4 year s o r 60,00 0
mile s (96,00 0 km) , whicheve r come s first , o r wheneve r
th e fue l pressur e drop s belo w th e specifie d valu e [32 4 -
36 3 kP a (3. 3 - 3. 7 kgf/cm
2, 4 7 - 5 3 psi ) wit h th e fue l pres -
sur e regulato r vacuu m hos e disconnected ] afte r makin g
sur e tha t th e fue l pum p an d th e fue l pressur e regulato r
are OK .
1. Plac e a sho p towe l unde r an d aroun d th e fue l filter .
2 . Reliev e fue l pressur e (se e pag e 11-132 ).
3 . Remov e th e 1 2 m m banj o bol t an d th e fue l fee d
pip e fro m th e filter .
4 . Remov e th e fue l filte r clam p an d fue l filter .
5 . Whe n assembling , us e ne w washer s a s shown .
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Fuel Suppl y Syste m
Fuel Pum p
Testin g
Do no t smok e durin g th e test . Kee p ope n
flam e awa y fro m you r wor k area .
I f yo u suspec t a proble m wit h th e fue l pump , chec k tha t
th e fue l pum p actuall y runs . Whe n it i s ON , yo u wil l hea r
some nois e if yo u hol d you r ea r t o th e fue l fil l por t wit h
the fue l fil l ca p removed . Th e fue l pum p shoul d ru n fo r
tw o second s whe n th e ignitio n switc h i s firs t turne d on .
I f th e fue l pum p doe s no t mak e noise , chec k a s follows :
1 . Remov e th e bulkhea d panels .
2 . Tur n th e ignitio n switc h OFF , the n disconnec t th e
C48 6 (6P ) connecto r (locate d behin d th e bulkhea d
panels).
3. Disconnec t th e PGM-F I mai n rela y connecto r an d
connec t th e No . 2 termina l an d No . 5 terminal * wit h
a jumpe r wire . * : 8 P connecto r
8P
Wir e sid e o f femal e terminal s
4. Chec k tha t batter y voltag e i s availabl e a t th e fue l
pum p connecto r whe n th e ignitio n switc h i s turne d
O N (positiv e prob e t o th e No . 3 terminal , negativ e
prob e to No . 6 termina l wire) .
C486 CONNECTO R (6P )
(BLK/YED -
(BLK)
If batter y voltag e i s available , replac e th e fue l
pump .
I f ther e i s n o voltage , chec k th e fue l pum p
groun d an d wir e harnes s (se e pag e 11-144 ).
Replacemen t
Do no t smok e whil e workin g o n fue l sys -
tem . Kee p ope n flame s awa y fro m you r wor k area .
1 . Remov e th e fue l tan k (se e pag e 11-147 ).
2 . Disconnec t th e connecto r fro m th e fue l pump .
3 . Remov e th e fue l pum p mountin g nuts .
4 . Remov e th e fue l pum p fro m th e fue l tank .
27 N- m (2. 8 kgf-m , 2 1 Ibf-ft )
5.9 N- m (0. 6 kgf-m ,4.3 Ibf-ft )
FUEL PUM P FUE
L PUM P
BRACKE T
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PGM-FI Main Relay

Description

The PGM-FI main relay actually contains two individual

relays.

The relay is located behind the passenger's seat back

panel.

One relay is energized whenever the ignition is on which

supplies the battery voltage to the ECM, power to the

fuel injectors, and power for the second relay.

The second relay is energized for 2 seconds when the

ignition is switched on, and when the engine is running

which supplies power to the fuel pump.

PGM-FI

MAIN RELAY
FUEL PUMP

RESISTOR

FUEL PUMP

FUEL

PUMP

RELAY
Relay Testing

NOTE: If the car starts and continues to run, the PGM-FI

main relay is OK.

1. Remove the PGM-FI main relay.

2. Attach the battery positive terminal to the No. 3*

terminal and the battery negative terminal to the

No. 2* terminal of the PGM-FI main relay. Then

check for continuity between the No. 5* terminal and

No. 2 terminal of the PGM-FI main relay.

If there is continuity, go on to step 3.

If there is no continuity, replace the relay and

retest.

3. Attach the battery positive terminal to the No. 4 ter-

minal and the battery negative terminal to the No.

7* terminal of the PGM-FI main relay. Then check

that there is continuity between the No. 3 terminal

and No. 1 terminal of the PGM-FI main relay.

If there is continuity, go on to step 4.

If there is no continuity, replace the relay and

retest.

4. Attach the battery positive terminal to the No. 1 ter-

minal and battery negative terminal to the No. 2*

terminal of the PGM-FI main relay. Then check that

there is continuity between the No. 5* terminal and

No. 2 terminal of the PGM-FI main relay.

If there is continuity, the relay is OK;

If the fuel pump still does not work, go to

Harness Testing in the next column.

If there is no continuity, replace the relay and

retest.

(cont'd)ProCarManuals.com

Fuel Suppl y Syste m
PGM-F I Mai n Rela y (cont'd )
Troubleshootin g
Engine wil l no t start .
Inspectio n o f PGM-F I mai n
rela y an d rela y harness .
Chec k fo r a n ope n i n th e wir e
(PG 1 line) :
1. Tur n th e ignitio n switc h OFF .2. Disconnec t th e PGM-F I mai n
rela y 4 P connecto r an d 8 P
connector .3. Chec k fo r continuit y betwee n
th e PGM-F I mai n rela y 8 P
connecto r termina l No . 7 an d
bod y ground .
I s ther e continuity ?
Chec k fo r a n ope n o r shor t i n th e
wir e (BA T line) :
Measur e voltag e betwee n th e
PGM-F I mai n rela y 4 P connecto r
terminal No . 3 an d bod y ground .
Is ther e batter y voltage ?
Chec k fo r a n ope n o r shor t i n th e
wir e (IGS W line) :
1. Tur n th e ignitio n switc h O N (II) .2. Measur e voltag e betwee n th e
PGM-F I mai n rela y 8 P connec -
tor termina l No . 5 an d bod yground .
PGM-FI MAI N RELA Y 8 P CONNECTO R
PG1(BLK )
Wire sid e o f femal e terminal s
Repai r ope n i n th e wir e betwee n
th e PGM-F I mai n rela y an d G10 1
(locate d a t righ t middl e o f
engine) .
Replac e th e ACG(S ) (2 0 A )
fus e i n th e engin e compart -
men t fuse/rela y box .
Repai r ope n o r shor t i n th e
wir e betwee n th e PGM-F Imain rela y an d th e ACG(S )
(2 0 A ) fuse .
I s ther e batter y voltage ?
(T o pag e 11-145 ) Replac
e th e No . 2 FUE L
PUMP , SR S 2 (1 5 A ) fus e i n
th e under-das h fus e box .
Repai r ope n o r shor t i n th e
wir e betwee n th e PGM-F I
mai n rela y an d th e No . 2 FUE L
PUMP , SR S 2 (1 5 A ) fuse .
ProCarManuals.com

(From pag e 11-144 )
Chec k fo r a n ope n i n th e wir e
(IGS W line) :
Measur e voltag e betwee n th e
PGM-F I mai n rela y 4 P connecto r
termina l No . 4 an d bod y ground .
I s ther e batter y voltage ? Replac
e th e I G COI L (3 0 A )
fus e i n th e engin e compart -
men t fuse/rela y box .
Repai r ope n o r shor t i n th e
wir e betwee n th e PGM-F I
mai n rela y an d th e I G COI L
(3 0 A ) fuse .
Chec k fo r a n ope n o r shor t i n th e
wir e (ST S line) :
1 . Tur n th e ignitio n switc h t o th e
STAR T (III ) position .
NOTE:• M/T : Clutc h peda l mus t b e
depressed .
• A/T : Transmissio n in o r
position .
2 . Measur e th e voltag e betwee n
th e PGM-F I mai n rela y 8 P con -
necto r termina l No . 3 an d
bod y ground .
I s ther e batter y voltage ?
Replace th e No . 7 STARTE RSIGNAL (7. 5 A ) fus e i n th eunder-das h fus e box .Repai r ope n o r shor t i n th e
wir e betwee n th e PGM-F I
mai n rela y an d th e No . 7
STARTE R SIGNA L (7. 5 A ) fuse .
Chec k fo r a n ope n i n th e wir e
(FLR 1 line) :1. Tur n th e ignitio n switc h OFF .
2 . Disconnec t th e EC M connec -
to r A (26P ) fro m th e ECM .
3 . Chec k fo r continuit y betwee n
th e PGM-F I mai n rela y 8 P
connecto r termina l No . 2 an d
EC M connecto r termina l A4 .
I s ther e continuity ? Repai
r ope n in th e wir e betwee n
th e EC M (A4 ) an d th e PGM-F I
mai n relay .
(cont'd )(To pag e 11-146 )
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Fuel Suppl y Syste m
PGM-F I Mai n Rela y (cont'd )
(From pag e 11-145 )
Chec k fo r a n ope n i n th e wire s
(IG P lines) :
1 . Reconnec t th e EC M connecto r
A (26P) .2. Reconnec t th e PGM-F I mai n
rela y 4 P an d 8 P connectors .
3 . Tur n th e ignitio n switc h O N (II) .
4 . Measur e voltag e betwee n
EC M connecto r terminal s A1 3
an d A12 , an d betwee n C 1 an d
A12 .
Is ther e batter y voltage ? Repai
r ope n i n th e wir e
betwee n th e EC M (A13 , C D
an d th e PGM-F I mai n relay .
Replac e th e PGM-F I mai n
relay.
Check fo r a n ope n in th e ECM :
1 . Tur n th e ignitio n switc h OFF .
2 . Measur e voltag e betwee n
EC M connecto r terminal s A 4
an d A1 2 whe n th e ignitio nswitch i s firs t turne d o n (II ) fo r
tw o seconds .
I s ther e 1. 0 V or less ? Substitut
e a known-goo d EC M
an d rechec k (se e pag e 11-3 9 fo r
immobilize r information) . I f pre -
scribe d voltag e i s no w available ,
replac e th e origina l ECM .
Chec k th e PGM-F I mai n rela y
(se e pag e 11-143 ).
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