1996 ACURA RL KA9 Service Repair Manual

PGM-FI System

Fuel Supply System (cont'd)

— The MIL has been reported on.

— DTC P0171, P0172, P0174 and/

or P0175 are stored.

Check the fuel pressure.

Is the fuel pressure OK?
NO

YES

Check the Primary HO2S:

1. Start the engine. Hold the

engine at 3,000 rpm with no

load (in Park or neutral) until

the radiator fan comes on.

2. Check the right primary or left

primary* HO2S (Sensor 1) out-

put with the scan tool.
Is the fuel pressure too high

or too low?
Check the fuel pressure regulator

and fuel return pipe.

LOW

Check the fuel pump, fuel feed

pipe, fuel filter, and fuel pressure

regulator.

Does it stay at less than 0.3 V

or more than 0.6 V?
Replace the HO2S.

NO

Check for a sticking or leaking

EVAP canister purge valve:

With a vacuum pump, apply vacu-

um to the EVAP canister purge

valve from the intake manifold

side.

Does it hold vacuum?

('96 model only)
Replace the EVAP canister purge

valve.

YES

Check the MAP sensor output:

1. Turn the ignition switch ON (II).

2. Check the MAP with the scan

tool.

Does it indicate atmospheric

pressure?
YES

*: P0174 or P0175
Check the response of the MAP

sensor:

1. Start the engine.

2. Check the MAP with the scan

tool.

Is a MAP of 40.0 kPa (300 mmHg,

12.0 inHg) or less indicated within

one second after starting the

engine?
Replace the MAP sensor.

YES

Check the EGR system. If it is OK,

replace the fuel injectors.
NO
NO

Replace the MAP sensor.
NO
YES
HIGH
Troubleshooting FlowchartProCarManuals.com

The sca n too l indicate s Diagnosti c Troubl e Cod e (DTC ) P0325 : A proble m in th e Righ t Knoc k Senso r (Ban k 1 ) cir -
cuit .
The sca n too l indicate s Diagnosti c Troubl e Cod e (DTC ) P0330 : A proble m in th e Lef t Knoc k Senso r (Ban k 2 ) cir -
cuit .
— Th e MI L ha s bee n reporte d on .
— DT C P032 5 and/o r P033 0 ar e
stored .
Proble m verification :1. D o th e PC M Rese t Procedure .2. Star t th e engine . Hol d th eengin e a t 3,00 0 rp m wit h n oloa 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 .
3 . Hol d th e engin e a t 3,00 0 -
4,00 0 rp m fo r 1 0 seconds .
Is DT C P032 5 and/o r P033 0indicated ?
YES
Chec k fo r a shor t i n th e wir e
(knoc k senso r line) :
1 . Tur n th e ignitio n switc h OFF .
2 . Disconnec t th e knoc k senso r
sub-harnes s connector .
3 . Chec k fo r continuit y betwee n
PC M connecto r terminal s D 2
o r D13 * an d bod y ground .
I s ther e continuity ?
NO
Chec k fo r a n ope n i n th e wir e
(knoc k senso r line) :
Chec k fo r continuit y betwee n PC M
connecto r termina l D 2 o r D13 *
an d knoc k senso r connecto r ter -
mina l No . 1 o r No . 3* .
I s ther e continuity ?
YES
Substitut e a known-goo d righ t o r
lef t knoc k senso r an d recheck .
I s DT C P032 5 and/o r P033 0
indicated ?
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 .
NO
Intermitten t failure , syste m is O K
a t thi s tim e (tes t driv e ma y b e
necessary) . Chec k fo r poo r con -
nection s o r loos e wire s betwee n
C25 1 (locate d a t lef t shoc k
tower) , C11 0 (locate d a t lef t rea r
corne r o f engine) , C162* , C16 3
(knoc k sensor ) an d PCM .
PCM CONNECTO R D (22P )
Repai r shor t i n th e wir e betwee n
PC M (D 2 o r D13* ) an d knoc k sen -
sor.
Wir e sid e o f femal e terminal s
Repai r ope n in th e wir e betwee n
PCM (D 2 o r D13* ) an d knoc k sen -sor.
KNOC K SENSO RCONNECTO RReplace th e origina l knoc k sensor .
Wire sid e o f femal e terminal s
*: P033 0
NO
N
O
YE S
Knoc k Senso r
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