1997 ACURA NSX Service Repair Manual

Ignition System

Ignition Coils/Spark Plugs Removal

CAUTION:

Ignition coils and spark plugs can become very hot in

use; do not touch them until the engine has cooled

down.

1. Remove the ignition coil covers.

2. Disconnect the 3P connectors from the ignition

coils.

3. Remove the ignition coils.

4. Remove the spark plugs.
NOTE: Different ignition coils and ignition coil

covers are used for the front and rear cylinders. Be

sure to use the correct ones when mounting them.

IGNITION COIL COVER

RUBBER

SEAL

PLATINUM TIP SPARK PLUG

CYLINDER HEAD

COVER
3P CONNECTOR

IGNITION COILProCarManuals.com

Ignition Coi l Tes t
1. Wit h th e ignitio n switc h OFF , remov e th e ignitio n
coil.
2. Usin g a n ohmmeter , measur e resistanc e betwee n
th e terminals . Replac e th e coi l i f th e resistanc e i s
no t withi n specifications .
NOTE: Resistanc e wil l var y wit h th e coi l
temperature ; specificatio n i s a t 77° F (25°C) .
Primary Windin g Resistanc e
(Betwee n th e A an d B terminals) : 0.9 - 1. 1 ohm s
3. I f primar y windin g resistanc e i s OK , substitut e aknown-goo d ignitio n coil , an d chec k th e syste m
operation .
If th e syste m is normal , replac e th e origina l ignitio n
coil.
A TERMINA L
B TERMINA LIGNITIONCOIL
SECONDAR Y
WINDINGTERMINA L
SPARK PLU G
VOLTAG E
SENSO R
SECONDAR Y
WINDINGTERMINA L
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Ignition System

Spark Plug Inspection

1. Inspect the electrodes and ceramic insulator for:

Worn or deformed

electrodes

Cracked

insulator

Burned or worn electrodes may be caused by:

Advanced ignition timing

Loose spark plug

Plug heat range too hot

Insufficient cooling

Fouled plug may be caused by:

Retarded ignition timing

Oil in combustion chamber

Incorrect spark plug gap

Plug heat range too cold

Excessive idling/low speed running

Clogged air cleaner element

Deteriorated ignition coil
2. Replace the plug if it is fouled or worn. Do not use

spark plugs other than those listed below.

Spark Plug:

PFR6L-11 (NGK)

PK20PR-L11 (DENSO)

3. Make sure that the 1.3 mm (0.051 in) plug gauge

does not go into the gap for the platinum tip plug. If

the gauge goes into the gap, do not attempt to

adjust the side electrode; replace the plug with a

new
one.

Electrode Gap:

Platinum tip plug:

Check and confirm that the

1.3 mm (0.051 in) plug

gauge does not go into the

gap.

Anti-seize compound

applied to threads

4. Apply a small quantity of anti-seize compound to

the plug threads before installing each plug. Screw

the plugs into the cylinder head finger-tight, then

torque them to 18 N-m (1.8 kgf-m, 13 Ibf-ft).
Improper gap

Oil-fouling

Carbon deposits

Cracked center

electrode insulator
Damaged

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Noise Condenser Capacity Test

1. Use a commercially available condenser tester.

Connect the tester probes, and measure the con-

denser capacity.

Condenser capacity: 0.47 ±0.09 microfarads

POSITIVE TERMINAL

BODY GROUND

(Negative)

NOTE: The noise condenser is intended to reduce

ignition noise. However, condenser failure may

cause the engine to stop running.

2. If not within the specifications, replace the noise

condenser.ProCarManuals.com

Charging Syste m
Componen t Locatio n Inde x
CHARGIN G SYSTE M LIGH T
(Buil t int o th e gaug e assembly )
Test, pag e 23-10 0
BATTER YTest, pag e 23-6 8
ALTERNATO R BEL T
Adjustment , pag e 23-10 9
ALTERNATO R• Alternato r an d Regulato r Test , pag e 23-10 2
• Replacement , pag e 23-10 5
• Overhaul , pag e 23-10 6
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Charging Syste m
Troubleshootin g
If th e chargin g syste m ligh t i s on , o r th e batter y i s dea d o r low , tes t th e followin g item s i n th e orde r listed :
1. Batter y (se e pag e 23-68 )
2 . Chargin g Syste m Ligh t
3 . Alternator/Regulato r
Charging Syste m Ligh t Tes t
Doe s th e chargin g syste m ligh t
com e on ?
Star t th e engine .
Does th e chargin g syste m ligh tgo off ?
Turn th e ignitio n switc h off .
Disconnec t th e 4 P connecto r
fro m th e alternator .
Turn th e ignitio n switc h O N (II) .
WHT/BL U wir e i s OK ; perfor m
alternator/regulato r tes t (se e pag e
23-102 ).
(T o page 23-101 )
Chargin g syste m ligh t circui t i s
OK .
Disconnec t th e AB S contro l uni t
(C235) , EP S contro l uni t (C249) ,
an d th e integrate d contro l uni t
(C401) , a s applicable . I f th e
chargin g syste m ligh t stay s on ,
repai r th e shor t t o groun d i n th e
WHT/BL U wire .
Does th e chargin g syste m ligh tcom e on ?
Tur
n th e ignitio n switc h O N (II) .
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(From page 23-100 )
I s th e fus e OK ?
Disconnec t th e 4 P connecto r
fro m th e alternator .
Tur n th e ignitio n switc h O N (II) .
Chec k fo r voltag e in th e YE L wir e
a t th e I G termina l o f th e 4 P con -
nector .
Is ther e batter y voltage ?
Groun d th e WHT/BL U wir e a t th e
L termina l o f th e 4 P connector .
Doe s th e chargin g syste m
light com e on ?
Perfor m alternator/regulato r tes t
(se e pag e 23-102 ). Replac
e th e fuse .
Repai r ope n in th e YE L wire .
Chec k fo r a blow n chargin g sys -
tem ligh t bulb . I f th e bul b is OK ,repai r ope n in th e WHT/BL U wire .
(cont'd )
Turn th e ignitio n switc h off .
Chec k fus e No . 2 (1 5 A) .
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Charging System

Troubleshooting (cont'd)

Alternator/Regulator Test

Use the SUN VAT-40 (or equivalent) tester.

LOAD ADJUSTER

(CARBON PILE)
FULL FIELD

LEAD (BLU)

VOLTMETER

NEGATIVE

LEAD (BLK)

INDUCTIVE

PICK-UP

(GRN)
POSITIVE

CABLE (RED)
NEGATIVE

CABLE (BLK)
VOLTMETER

POSITIVE

LEAD (RED)

1. Attach the positive tester cable and the voltmeter

positive lead to the jump start terminal in the

engine compartment fuse/relay box.

POSITIVE CABLE

VOLTMETER

POSITIVE LEAD

JUMP

START

TERMINAL

ENGINE COMPARTMENT

FUSE/RELAY BOX
2. Attach the negative tester cable and the voltmeter

negative lead to the top of the intake manifold.

VOLTMETER

NEGATIVE LEAD
NEGATIVE CABLE

NEGATIVE MARK

3. Attach the inductive pick-up to the B terminal wire

of the alternator with its arrow pointing away from

the terminal.

NOTE: The arrow must point away from the B

terminal.

INDUCTIVE PICK-UP

ARROW
ALTERNATOR

B TERMINAL

ALTERNATORProCarManuals.com