1996 ACURA RL KA9 Service Repair Manual

PGM-FI Syste m
NOTE: I 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 P1486 , troubleshoo t thos e DTC s first , the n rechec k fo r
P1486 .
P0107 , P0108 , P1128 , P1129 : MA P Senso r
P1106 , P1107 , P1108 : Barometri c Pressur e Circui t
P1259 , P1279 : VTE C syste m
P0401 : EG R Flo w Insufficien t
P1491 : EG R Valv e Lif t Insufficien t
P1498 : EG R Valv e Positio n Senso r Hig h Voltag e
P0116 , P0117 , P0118 : Engin e Coolan t Temperatur e Circui t
P0112, P0113 : Intak e Ai r Temperatur e Circui t
P0335 , P0336 , P1336 , P1337 : Crankshaf t Positio n Senso r 1/ 2
P0300 : Rando m Misfir e
P0301 , P0302 , P0303 , P0304 , P0305 , P0306 : Cylinde r 1 , 2 , 3 , 4 , 5 or 6 Misfir e detected .
P0505 : Idl e Contro l Syste m Malfunctio n
P1508 : Idl e Ai r Contro l Valv e
DT C P148 6 ca n se t occasionall y whe n th e hoo d i s opened .
— Th e MI L ha s bee n reporte d on .
— DT C P148 6 is stored .
1. Tur n th e ignitio n Switc h OFF .2. Chec k th e engin e coolan t
level .
I s th e engin e coolan t leve l low ?
Doe s th e radiato r fa n kee p
running ?
YES
Chec k th e radiato r fa n circuit ,
radiato r fa n switc h circui t an d
th e radiato r fa n switch .
I t the y ar e OK , substitut e th e
PC M an d rechec k (se e pag e 11-42
fo r immobilize r information) .
I f th e symptom/indicatio n goe s
away , replac e th e origina l PCM . Refil
l th e engin e coolant . I f neces -
sary , chec k th e coolin g system .
Tes t th e thermostat .
NO
N
O
YE S
Chec k fo r th e radiato r fo r circuit :
1 . Tur n th e ignitio n switc h O N
(II).2. Chec k th e radiato r fan .
Troubleshootin g
('00 - 0 1 model ) Th e sca n too l indicate s Diagnosti c Troubl e Cod e (DTC ) P1486 : Range/Performanc e Proble m in
Thermostat .
Thermostat
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PCM Interna l Circui t
— Th e MI L ha s bee n reporte d on .
— DT C P160 7 is stored .
Proble m verification :
1 . D o th e PC M Rese t Procedure .
2. Tur n th e ignitio n switc h O N (II) .3. Allo w it t o 3 seconds .
I s DT C P160 7 indicated ? Intermitten
t failure , syste m is O K
a t thi s time .
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 -
tom/indicatio n goe s away , replac e
th e origina l PCM .
The sca n too l indicate s Diagnosti c Troubl e Cod e (DTC ) P1607 : A PC M Interna l Circui t Failure .
NO
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Idle Contro l Syste m
System Descriptio n
The idl e spee d o f th e engin e is controlle d b y th e Idl e Ai r Contro l (IAC ) Valve .
Th e valv e change s th e amoun t o f ai r bypassin g int o th e intak e manifol d i n respons e t o electri c curren t controlle d b y th e
PCM . Whe n th e IA C Valv e is activated , th e valv e open s to maintai n th e prope r idl e speed .
VARIOU S
SENSOR S
INTAK E
MANIFOL D
IDLEADJUSTIN GSCREW
1. Afte r th e engin e starts , th e IA C valv e open s fo r a certai n time . Th e amoun t o f ai r i s increase d t o rais e th e idl e spee d
abou t 15 0 - 30 0 rpm .
2 . Whe n th e coolan t temperatur e i s low , th e IA C valv e i s opene d t o obtai n th e prope r fas t idl e speed . Th e amoun t o f
bypasse d ai r i s thu s controlle d in relatio n to th e engin e coolan t temperature .
3 . Whe n th e idl e spee d is ou t o f specificatio n an d th e sca n too l doe s no t indicat e Diagnosti c Troubl e Cod e (DTC ) P050 5 o r
P1508 , chec k th e followin g items :
• Adjus t th e idl e spee d (se e pag e 11-124 )
• Ai r conditionin g signa l (se e pag e 11-116 )
• AL T F R signa l (se e pag e 11-118 )
• Starte r switc h signa l (se e pag e 11-119 )
• Transmissio n rang e signa l (se e sectio n 14 )
• PS P switc h signa l (se e pag e 11-120 )
• Brak e peda l positio n switc h signa l (se e pag e 11-122 )
• Idl e ai r contro l therma l valv e (se e pag e 11-123 )
• Hose s an d connection s
• IA C valv e an d it s mountin g O-ring s
4 . I f th e abov e item s ar e normal , substitut e a known-goo d IA C valv e an d readjus t th e idl e spee d (se e pag e 11-124 ).
I f th e idl e spee d stil l canno t b e adjuste d t o specificatio n (an d th e sca n too l doe s no t indicat e DT C P050 5 o r P1508 ) afte r
IA C valv e replacement , 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
sympto m goe s away , replac e th e origina l PCM .
IDLEAIRCONTRO LTHERMA LVALVE
IAC VALV E
FromPGM-F IMAINRELA Y
ENGIN E COOLAN T
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Idle Contro l Syste m
NOTE: I f DT C P150 8 is store d a t th e sam e tim e a s DT C P0505 , troubleshoo t DT C P150 8 first , the n troubleshoo t DT C P0505 .
Possibl e Caus e
• IA C valv e mechanica l malfunctio n
• Idl e ai r contro l therma l valv e malfunctio n
• Throttl e bod y clogge d port , imprope r adjustmen t
• Intak e manifol d gaske t leakag e
• Intak e ai r hos e loos e o r leakin g
• Vacuu m hose s leakag e
• EC T senso r incorrec t outpu t
• Throttl e Positio n senso r incorrec t output *
•: '9 6 mode l onl y
— Th e MI L ha s bee n reporte d on .
— DT C P050 5 is stored .
Proble m verification :
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
(in Par k or neutral ) untilthe radiato r fa n come s on ,then le t i t idle .
2 . Wit h th e sca n tool , chec k th e
followin g item s ('9 6 mode l
only) .
— Throttl e positio n shoul d b e
abou t 10 % wit h th e throttl e
fully closed .— Engin e coolan t tempera -
tur e shoul d b e abou t 17 6 -
194° F (80-90°C) .
I f the y ar e no t withi n th e spec. ,
repai r th e fault y senso r circuit .
3 Chec k th e engin e spee d a t
idl e wit h no-loa d conditions :
headlights , blowe r fan , rea r
defogger , radiato r fan , an d ai r
conditione r ar e no t operating .
Is i t 65 0 5 0 rpm ?
NO
Is i t 60 0 rp m o r less ?
YES
Intermitten t failure , syste m is O Kat thi s time .
NO
(T o pag e 11-114 ) (T o pag e 11-114 )
YES
The sca n too l indicate s Diagnosti c Troubl e Cod e (DTC ) P0505 : Idl e contro l syste m malfunction .
Troubleshootin g Flowchar t
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