ACURA RL KA9 1996 Service Repair Manual

Intake Manifol d Runne r Contro l (IMRC ) Syste m
Descriptio n
Satisfactor y powe r performanc e i s achieve d b y closin g an d openin g th e intak e manifol d runne r contro l (IMRC ) valves .
Hig h torqu e a t lo w RP M is achieve d whe n th e valve s ar e closed , wherea s hig h powe r a t hig h RP M is achieve d whe n th e
valve s ar e opened .
INTAKE MANIFOL D RUNNE R CONTRO L
(IMRC ) SOLENOI D VALV E 1 OF F INTAK
E MANIFOL D RUNNE R CONTRO L
(IMRC ) SOLENOI D VALV E 2 OF F
ENGIN E SPEE D IS ABOV E 3,20 0 rp m
ENGINE SPEE D IS ABOV E 3,80 0 rp m
IMR C SOLENOI D VALV E 2
IMR C
SOLENOI D
VALVE !
IMR C
DIAPHRAG M 1
VARIOU SSENSOR S
IMRC
VALVE 1: CLOSED IMRC
VALVE 2: CLOSED
IMR C
VALV E 2
IMR C
DIAPHRAG M 2
IMR C
VALV E 1 IMR
C
DIAPHRAG M 1
IMR C
VALV E 1 : OPE N
IMR C
VALV E 2 : CLOSE D IMR
C
VALV E 1 : OPE N
IMR C
VALV E 2 : OPE N
From No . 2 0 EC U(PCM ) (20 A )FUS E
(i n th e under-das h
fuse/rela y box )
Fro
m PGM-F I
MAI N RELA Y
IACVALV E
ENGIN ECOOLAN T
VACUU
M
RESORVOI R
IMRC
DIAPHRAG M 2 VACUU
M
CHECKVALV E
INTAK E
MANIFOL DTHROTTL
E BOD Y
IDL
E AI R
CONTRO L
THERMA L
VALVEIDLEADJUSTIN GSCREWINTAK EAIRDUC T
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Intake Ai r Syste m
Intake Manifol d Runne r Contro l (IMRC ) Syste m (cont'd )
Troubleshootin g Flowchar tNo. 2 VACUU MHOSE
Inspectio n o f IMR C System .
Chec k fo r vacuu m at idle :
1. Star t engin e an d allo w it t oidle .2. Remov e No . 2 vacuu m hos e
fro m th e IMR C diaphragm , an d
connec t vacuu m gaug e t o th e
hose .
Is ther e vacuum ?
YES
VACUU M PUMP /
GAUGE , 0 - 3 0 in.H g
A973 X - 04 1 -
XXXX X
Chec k fo r vacuu m at IMR C vacu -
um Resorvoir :Disconnec t th e No . 4 hos e o n
IMR C solenoid , an d connec t a
vacuu m gaug e t o th e hose .
I s ther e vacuum ?
YES
Chec k fo r a n ope n i n th e wir e
(IABCS 1 line) :
1 . Tur n th e ignitio n switc h OFF .
2 . Disconnec t th e 6 P connecto r
fro m th e IMRC/engin e moun t
contro l solenoi d valv e assy .
3 . Star t engin e an d allo w i t t o
idle .4. Measur e voltag e betwee n 6 P
connecto r termina l No . 2 an d
No. 5 .
Is ther e batter y voltage ?
NO
Chec k fo r a n ope n in th e wir e (IG 1
line) :
Measur e voltag e betwee n 6 P con -
necto r termina l No . 2 an d bod yground .
IMRCDIAPHRAG MVALVE 1
Repai r th e blockag e o r vacuu m
lea k betwee n th e IMR C vacuu m
reservoi r an d th e intak e mani -
fold .
IMRC/ENGIN E MOUN T CONTRO L SOLENOI D
VALV E ASSY . 6 P CONNECTO R (C108 )
Wir e sid e o f femal e terminal s
Replac e th e IMR C solenoi d valv e
1.
(T o pag e 11-159 ) (T
o pag e 11-159 )
NO
NO
YE S
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(From pag e 11-158 )
Chec k fo r vacuu m at idle :
Remov e No . 8 vacuu m hos e fro m
th e IMR C diaphrag m 2 an d con -
nec t a vacuu m gaug e to th e hose .
I s ther e vacuum ?
NO
YE S
(To pag e 11-160 ) I
s ther e batter y voltage ?
YES
Repai r ope n i n wir e betwee n th e
6 P connecto r an d No . 2 0 EC U
(PCM ) (2 0 A ) fus e i n th e under -
das h fuse/rela y box .
PC M CONNECTO R A (26P )
Chec k fo r a n ope n i n th e wir e
(IABCS 1 line) :1. Tur n th e ignitio n switc h OFF .2. Chec k fo r continuit y betwee n
PC M connecto r termina l A2 0
and bod y ground .
Wire sid e o ffemal eterminal s
Is ther e continuity ? Repai
r ope n i n wir e betwee n
PC M (A20 ) an d th e 6 P connector .
YES
Substitut e a known-goo d PC M
an d rechec k (se e pag e 11-42 fo r
immobilize r information) . I f symp -
to m goe s away , replac e th e origi -
nal PCM .
Check fo r vacuu m at IMR C vacu -
u m reservoir :
Disconnec t th e No . 4 hos e o n
IMR C solenoi d valv e 1 an d con -
nec t a vacuu m gaug e t o th e
hose .
VACUU M
PUMP /
GAUG EA973X - 04 1 -XXXX X
IMRCDIAPHRAG M 2
No . 8 VACUU MHOSE
Is ther e vacuum ?
YES
Repai r th e blockag e o r vacuu m
lea k betwee n th e IMR C vacuu m
resorvoi r an d th e intak e mani -
fold.
Chec k fo r a n ope n i n th e wir e
(IABCS 2 line) :
1 . Tur n th e ignitio n switc h OFF .
2 . Disconnec t th e 6 P connecto r
fro m th e IMRC/engin e moun t
contro l solenoi d valv e assy .
3 . Star t engin e an d allo w it t o
idle .4. Measur e voltag e betwee n 6 P
connecto r termina l No . 1 an d
No. 4 .
IAB/ENGIN E MOUN T CONTRO L SOLENOI D
VALV E ASSY . 6 P CONNECTO R (C108 )
Wir e sid e o f femal e terminal s
(T o pag e 11-160 )
NO
NO
N O
(Fro m pag e 11-158 )
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Intake Ai r Syste m
Intake Manifol d Runne r Contro l (IMRC ) Syste m (cont'd )
(From pag e 11-159 ) (Fro m pag e 11-159 )
I s ther e batter y voltage ?
YES
NO
Chec k fo r a n ope n in th e wir e (IG 1
line) :
Measur e voltag e betwee n 6 P con -
necto r termina l No . 1 an d bod y
ground .
Is ther e batter y voltage ? Replac
e th e IMR C solenoi d valv e
2.
IMRC/ENGIN E MOUN T CONTRO L SOLENOI DVALVE ASSY . 6 P CONNECTO R (C108 )
Wire sid e o f femal e
terminal s
Repai r ope n in wir e betwee n th e
6 P connecto r an d No . 2 0 EC U
(PCM ) (20A ) fus e i n th e under -
das h fuse/rela y box .
PC M CONNECTO R A (26P )
Wir e sid e o f femal e terminal s
NORepai r ope n i n wir e betwee n
PC M (A22 ) an d th e 6 P connector .
YESReplac e th e IMR C solenoi d valv e1.
(T o pag e 11-161 ) (T
o pag e 11-161 )
I
s ther e vacuum ?
I
s ther e vacuum ?
NO
YE S
Chec k th e IMR C Solenoi d Valv e1:Disconnec t th e 6 P connecto r fro m
th e IMRC/engin e moun t contro l
solenoi d valv e assembly .
Substitut
e a known-goo d PC M
an d rechec k (se e pag e 11-42 fo r
immobilize r information) . I f symp -
to m goe s away , replac e th e origi -
nal PCM .
Is ther e continuity ?
Chec
k fo r a n ope n i n th e wir e
(IABCS 2 line) :
1. Tur n th e ignitio n switc h OFF .2. Chec k fo r continuit y betwee n
PC M connecto r termina l A2 2
an d bod y ground .
YES
NO
YE SChec k fo r vacuu m at 3,40 0 rpm :
1 . Rais e engin e spee d t o 3,40 0
rpm.2. Chec k fo r vacuu m a t No . 2
vacuu m hose .
NO
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(From pag e 11-160 ) (Fro
m pag e 11-160 )
PCM CONNECTO R A (26P )
YES
Chec k fo r a shor t i n th e wir e
(IABSC 1 line) :
1. Tur n th e ignitio n switc h OFF .2. Disconnec t th e PC M connec -tor A (26P ) fro m th e PCM .3. Chec k fo r continuit y betwee n
PC M connecto r termina l A2 0
and bod y ground .
Is ther e continuity ?
NO
Substitut e a known-goo d PC M
an d rechec k (se e pag e 11-42 fo r
immobilize r information) . I f symp -
to m goe s away , replac e th e origi -
nal PCM .
Is ther e continuit y t o ground ?
NO
Substitut e a known-goo d PC Mand rechec k (se e pag e 11-42 fo r
immobilize r information) . I f symp -
to m goe s away , replac e th e origi -
nal PCM .
Wire sid e o f femal e terminal s
Repai r shor t t o groun d a t wire
betwee n PC M (A20 ) an d th e 4 Pconnector .
YESReplac e th e IMR C solenoi d valv e2.
Repai r shor t t o groun d a t wir ebetwee n PC M (A22 ) an d th e 4 Pconnector .
YES
NO
Chec k fo r a shor t i n th e wir e
(IABCS 2 line) :
1. Tur n th e ignitio n switc h OFF .2. Disconnec t th e PC M connec -tor A (26P ) for m th e PCM .3. Chec k fo r continuit y betwee n
PC M connecto r termina l A2 2
and bod y ground .IMRC syste m is OK .
NO
Is ther e vacuum ? Chec
k th e IMR C Solenoi d Valv e2:Disconnec t th e 6 P connecto r fro m
th e IMRC/engin e moun t contro l
solenoi d valv e assy .
YES
Chec k fo r vacuu m at 4,00 0 rpm :
1 . Rais e engin e spee d t o 4,00 0
rpm.2. Chec k fo r vacuu m a t No . 8
vacuu m hose .
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Intake Ai r Syste m
Intake Manifol d Runne r Contro l (IMRC ) Syste m (cont'd )
Intake Manifol d Runne r Contro l (IMRC ) Valv e 1 Testin g
1 . Disconnec t th e No . 2 hos e fro m th e vacuu m hos e
manifold , an d attac h a vacuu m pum p t o th e vacuu m
hos e manifold .
IMRC SOLENOI D VALV E 1
VACUU MPUMP/GAUG E
A973 X - 04 1 -
XXXX X
2. Appl y vacuu m an d verif y tha t th e IMR C diaphrag m
hold s vacuu m an d tha t a s th e vacuu m is applie d an d
release d th e IMR C diaphrag m ro d move s in an d out .
I f th e IMR C diaphrag m doe s no t hol d vacuu m o r th e
IMR C diaphrag m ro d doe s no t mov e i n an d out ,
replac e th e IMR C diaphrag m (se e sectio n 9 ) an d retest . Intak
e Manifol d Runne r Contro l (IMRC ) Valv e 2 Testin g
1 . Disconnec t th e No . 8 hos e fro m th e vacuu m hos e
manifold , an d attac h a vacuu m pum p t o th e vacu -
u m hos e manifold .
IMRC SOLENOI D VALV E 2
No . 8 HOS E
2. Appl y vacuu m an d verif y tha t th e IMR C diaphrag m
hold s vacuu m an d tha t a s th e vacuu m is applie d
an d release d th e IMR C diaphrag m ro d move s in an d
out.
If th e IMR C diaphrag m doe s no t hol d vacuu m o r th e
IMR C diaphrag m ro d doe s no t mov e i n an d out ,
replac e th e IMRC diaphrag m (se e sectio n 9 ) an d
retest .
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Intake Ai r Bypas s Contro l Syste m
Descriptio n
Th e Intak e Ai r Bypas s Contro l syste m enable s fres h ai r
t o b e draw n throug h th e throttl e bod y an d fue l injecto r
port.
INJECTO R
AI R FLO W FRO M TH E
IDL E AI R CONTRO L THERMA L VALV E
Testing
1 . Star t th e engine . Hol d th e engin e a t 3,00 0 rp m wit h
n o loa d i n Par k o r neutra l until the radiato r fa n
come s on .
2 . Disconnec t th e vacuu m hose s an d connec t vacuu m
pum p t o th e hose s individually .
VACUUM PUMP /GAUGE , 0 - 3 0 In.H gA973 X - 04 1 -
XXXX X
3. Allo w th e engin e t o idle , an d chec k th e vacuum .
• I f n o vacuum , chec k th e vacuu m hos e routin g o f
th e intak e ai r bypas s contro l system .
• I f th e vacuum , chec k th e IA C Valv e (se e pag e
11-115 ), th e Idl e Ai r Contro l Therma l Valv e (se e
pag e 11-123 ) an d th e intak e manifol d port . I f th e
intak e manifol d por t i s clogged , clea n it wit h car -
bureto r cleaner .
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Emission Contro l Syste m
System Descriptio n
The emissio n contro l syste m include s a Thre e Wa y Cata -
lyti c Converte r (TWC) , Exhaus t Ga s Recirculatio n (EGR )
system , Positiv e Crankcas e Ventilatio n (PCV ) syste m an d
Evaporativ e Emissio n (EVAP ) system . Th e emissio n contro l
syste m is designe d t o mee t federa l an d stat e emissio n
standards .
Tailpipe Emissio n
Inspection
Do no t smok e durin g thi s procedure . Kee p
an y ope n flam e awa y fro m you r wor k area .
1 . Star t th e engine . Hol d th e engin e a t 3,00 0 rp m wit h
n o loa d (i n Par k o r neutral ) unti l th e radiato r fa n
come s on , the n le t i t idle .
2 . Connec t a tachometer .
3 . Chec k an d adjus t th e idl e speed , i f necessar y (se e
pag e 11-124 ).
4 . War m u p an d calibrat e th e C O mete r accordin g to th e
mete r manufacturer' s instructions .
5 . Chec k idl e C O wit h th e headlights , heate r blower ,
rea r windo w defogger , coolin g fan , an d ai r condition -
er off .
NOTE : (Canada ) Depres s th e parkin g brak e pedal .
Star t th e engine , the n chec k tha t th e headlight s ar e
off.
CO mete r shoul d indicat e 0.1 % maximum .
Three Wa y Catalyti c Converte r
(TWC)
Descriptio n
Th e Thre e Wa y Catalyti c Converte r (TWC) is use d t o
conver t hydrocarbon s (HC) , carbo n monoxid e (CO) , an d
oxide s o f nitroge n (NOx) in th e exhaus t gas , t o carbo n
dioxid e (CO
2), dinitroge n (N2) an d wate r vapor .
SECONDAR Y HEATE D OXYGE N SENSO R (SENSO R 2)
HOUSIN G
THREE WA Y
CATALYST S
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The sca n too l indicate s Diagnosti c Troubl e Cod e (DTC ) P0420 : Catalys t syste m efficienc y belo w threshold .
Descriptio n
This syste m evaluate s th e catalyst' s capacit y b y mean s o f th e HO2 S (Primar y an d Secondary ) outpu t durin g stabl e drivin g
conditions . I f deterioratio n ha s bee n detecte d durin g tw o consecutiv e drivin g cycles , th e MI L come s o n an d DT C P042 0 wil l
be stored .
NOTE : I f som e o f th e DTC s liste d belo w ar e store d a t th e sam e tim e a s DT C P0420 , troubleshoo t thos e DTC s first , the n
troubleshoo t DT C P0420 .
P0136 , P0139 : Secondar y HO2 S
P0141 : Secondar y HO2 S Heate r
Possibl e Caus e
• TW C Deterioratio n
• Exhaus t syste m leakag e
Troubleshootin g Flowchar t
— Th e MI L ha s bee n reporte d on .
— DT C P042 0 is stored .
Proble m verification :
1 . D o th e PC M Rese t Procedure .
2 . Star t th e engine . Hol d th e
engin e a t 3,00 0 rp m wit h n o
loa d (i n Par k o r neutral ) unti l
th e radiato r fa n come s on .
3 . Connec t th e AC S servic e con -
nector .
4 . Test-driv e 4 0 - 5 5 mp h (6 4 -
8 8 km/h ) fo r approx . 2 min -
utes . The n decelerat e fo r a t
leas t 3 second s wit h th e throt -
tl e completel y closed . The n
reduc e th e vehicl e spee d t o
3 5 mp h (5 6 km/h) , an d tr y t o
hol d it unti l th e readines s cod e
come s on .
I s DT C P042 0 indicated ?
YES
Chec k th e TW C (se e sectio n 9 ).
I f necessary , replac e th e TWC . Intermitten
t failure , syste m is O K
at thi s time .
NO
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Emission Control System

Exhaust Gas Recirculation (EGR) System

Description

The EGR system is designed to reduce oxides of nitrogen emissions (NOx) by recirculating exhaust gas through the EGR

valve and the intake manifold into the combustion chambers. It is composed of the EGR valve, EGR valve vacuum control

valve, EGR valve vacuum control solenoid valve, PCM and various sensors.

The PCM contains memories for ideal EGR valve lifts for varying operating conditions. The EGR valve position sensor

detects the amount of EGR valve lift and sends the information to the PCM. The PCM then compares it with the ideal EGR

valve lift which is determined by signals sent from the other sensors. If there is any difference between the two, the PCM

cuts current to the EGR valve vacuum control solenoid valve to reduce vacuum applied to the EGR valve.

EGR VALVE

POSITION SENSOR
INTAKE MANIFOLD

From No. 20 ECU (PCM)

(20 A) FUSE

(in the under-dash

fuse/relay box)

VARIOUS

SENSORS

EGR VALVE

EGR VALVE

VACUUM

CONTROL

SOLENOID

VALVE
EGR VALVE

VACUUM

CONTROL

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