ACURA INTEGRA 1994 Service Repair Manual

Fuel Supply System
Fuel Injectors
- --l- - \-l-l
116l- -ltc l-/---r- / ---i- \
The Fuel Injectors a.e a solenoid-actuated constant-stroke pintle type consisting of a solenoid, plungel n€edle valvs and
housing. When cur.ent is applied to the solsnoid coil, the vslve litts up and pressurized fuel is injected. Because the nee-
dle valve litt and the luel pressure are constant, the iniection quantity is determined by the length of time that the valv€
is open (i.e., the duration the cu.rent is supplied to the solenoid coill. The Fu€l Iniector is sealed by an O-ring and seal
ring at the top and bottom. These seals also reduce operating nois6.
O.RII{G FUEL RAIL
The Malfunction Indicator Lamp (MlL) indicates Diagnostic Trouble Code (DTC) l6: A problem in
the Fuel lniector circuit.
FILTER
PTUNGER
-_-- - ___L-
IrGl- lto l--|.---:_-
- Tho MIL has boen roportod on.- Wilh tho SCS .hon connocto.conoctod (soo pago 11-34),code 16 is indicalod.
Do the ECM Besel Procedure (seepage l l -351.
Intermittant tailura, aystam ir OKat thir tim. (t..1 drivo m.y b.nocaar!ry1.Ch.ck lor poor connactiona ot100!6 wir6!.t C221 (loortod rtright .hock low.rl, C121,C122,Cl23, Cl24 llu6l InFctorrl, lndECM.
ls the MIL on and does itindicate code l6?
NOTE: lf engine willnot start, it may tak6lO seconds ol cranking to sgt th6 code.
{To page 1 1-1O31
11-102

lFrom psge 1 1-1021
(To p6ge I l-1O41
St6n the enoin€ 8nd listgn at oachfuol inioctor fo. a clicking sound.
Turn the ignition switch OFF.
Disconnoct tho 2P cohnector fromth6 lu€l iniocto. th6l does notclick.
Mossur€ rggistance batwson th€
2 terminalE ol fuol injocto..
R.phce tho fuol ini.ctor/lni.ctor!that ar€ not 10- 13 O.ls thoro 1O- 13 07
T!.n tho ignition switch ON.
Moaaur€ voltage b€tweonYEL/BLK { + I terminsl in ths 2Pconnoctor and body ground.
B.prh op.n In tho YEL/BLK wlt6botwaan tha luol inioctor aad lhaPGM- Fl main r.lsy.ls thore battory volt6g€7
FUELII{JECTOR
(cont'd)
11-103

Fuel Supply System
Fuel Injectors (cont'd)
(From page 'l1-103)
Turn lhe ignition switch OFF.
Reconnect the 2P connector tothe tuel injector.
Connect the test harness betweenrhe ECM and connectors {seopage'11-371.
Turn the ignition switch ON.
Measure voltage between A23{-) terminal and followingterminal:. No. 1 tuel injector:A1 (+ ) terminal.. No. 2 fuel injector:A3 {+ I terminal.. No. 3 fuel injector:A5 {+ ) terminal.. No. 4 fuel injector:A2 {+ ) terminal.
Ropair opon in the wi.o betw6onth6 ECM (A1, A3, A5 or A2l andth6 tuel iniector.
Sub3titute a known-good ECMand r6chock. lf symptom/indica-tion goes away, .eplsco tho origi-nal ECM.
oooooooooo
oooooooooooooooooooo
oooooooo
ooooooooooo
ooooooooooo
A3{+)
A2{+}
11-104

Rapl!c!ment
@ oo not smoko during tho work. Keep open
fllma3 lway from your wolk aloa.
1. Retieve tuel pressure {see page 1 1-10O).
2. Disconnect the connectors trom the fuel iniectors.
3. Disconnect the vacuum hose and fuel return hosa
from the fuel pressure regulatol.
NOTE: Place a r8g or shop towel over the hoses be-
for6 disconnecting them.
4. Loosen the retainer nuts on the Juel rail and harness
holder.
Disconnect the tuel 18il.
Remove the fuel injectors from the intake manifold.
5.
6.
cusHloNRINGReplace.
FUEL
7.
t'.
9.
10.
13.
14.
16.
11.
Slide new cushion rings onto the luel iniectors.
Coat new O-rings with clean engine oil and put them
on the fuel injectors.
Insen the injectors into the tuel rail tirst.
Coat new seal rings with clean engine oil and press
them into the intake manifold.
Install the Juel iniectors and fuel rail assembly in the
intake manilold.
CAUTION: To plovont damage to th€ O-dngs, instsll
tho fuol inioctors in tho fuol r8il first, thon install th€m
in the intaks mEnitold.
12. Align the center line on the connector with the mark
on the fuel rail.
FUEI. RAIL
MABKI'{GS
Install and tighten the retainer nuts
Conn€ct the vacuum hose and tuel retuln hose to
the fuel pressure regulator.
lnstall the connecto.s on the fuel injectors.
Turn the ignition switch ON, but do not operate the
starte.. After the tuel pump runs for approximately
two seconds, the tuel pressure in the fuelline rises.
ReDeat this two or three times, then check whether
there is any fuel leakage
11-105

Fuel Supply System
Fuel Pressure Regulator
FUELRETURI{
Description
The fuel pressure .egulator maintains a constant Juel
pressure to the tuel injectors. When the difference be-
tween the fuel pressure and manitold pressur€ exceeds
3.O kgf/cm' 1294 kPa, 43 psi) tB18C1 engine: 3.5
kgt/cm, (343 kPa, 50 psi)], the diaphragm is pushed up-
ward, and the excess fuel is fed back into the fuel tank
through the retufn line,
CLOSE:
DIAPHRAGM
__l FUEL INLET
INTAKEMA'{IFOLDVACUUM
DIAPHNAGM
/1-
\J FUEL INLET
11-106
Te6ting
@ oo not smoko during the t€st. Ko6p opon
flames away from your work area,
1. Attach a fuel pressure gauge to the se.vice port of
the luel filter {see page 11-101).
Prossuro should be;
Bl88l ongin€:
275-324 kPa (2.8-3.3 kgf/cm', 40-47 psil
B18Cl €ngino:
329-378 kPa (3.35-3.85 kgf/cm'.48-55 pEi)
(with tho tuol pressure rsgulator vacuum hoso dls-
connoctod and pinched)
FUEL PRESSURE GAUGE07406 - oO/IOOO 1
Reconnect the vacuum hose to the fuel pressure
regulator.
Check that the tuel pressure rises when the vacu-
um hose from the fuel pressure regulator is discon-
nected again.
a lf the fuel pressure did not rise, replace the fuel
pressure regulatot.

Raplacoment
@ oo not amoko whil6 working on fuel sys-
tam. Koop open flamo away tlom your work atea'
1. Place a shop towel under the fuel pressure regula-
tor, then reliev€ tuel pressure (see page 1l-10O).
2. Disconnect the vacuum hose and fuel return hose.
3. Remove the two 6 mm retainer bolts.
12 N.m{1.2 kgl.m,9 rbf.ft)
NOTE:
a Replaco the O-ring.
a When assembling the fuel pressure regulator, ap-
ply clean engine oil to the O-ring and assemble
it into its proper position, taking care not to
damage the O-dng.
Rsplace.
11-107

Filter
Fuel Supply System
Fuel
a Do not smoko while wo*ing on tusl system.
Keop open tlame away ftom your wotk area.a While replaclng th6 tusl liher, be caletul to koop a safodistanc6 betweon battery torminals and any tool3.
The Juel filter should b€ replaced every 4 years or 60,0O0miles (96,OOO km), whichever comes f irst. or wheneverthe fuel pressure drops below the specilied value
127 5 - 324 kPa, 2.8 - 3. 3 kgJ/cmr, 40-47 psi (Bl 8C 1engine: 329-378 kPa, 3.35-3.85 kgf/cmr, 48-55psi) with the fuel pressure regulator vacuum hose dis-
connectedl afte. making sure that the tuel pump and thefuel pressure regulator are OK.
1 , Disconnect the battery negative cable trom the bat-
tery negative terminal.
NOTE; The LS and GS-R model radio may have acoded theft protection circuit, Be sure to get the cus-
tomer's code number before disconnecting the
batterv.
After service, reconnect power to the tadio and turn
it on. When the word "CODE" is displaved, enter
the customer's 5-digit code to restore radio
operation.
2. Place a shop towel under and around the fueltilter.
3. Relieve fuel pressure (see page 11-100).
4. Remove the special banio bolt and the fuel feed pipe
from the fuel tilter.
Remove the fuel filter clamp and tuel Jilter.
When assembling, use new washers, as shown,
NOTE: Clean the llared joint ot high pressure hoses
thoroughly before reconnecting them,
1 1-108
SPECIALBOLT33 N.m(3.4 kgt.h,25 rbf.ft)
SERVICE BOLT15 N.m ll.5 kgt.m,1 I rbr.ftl
WASHERReplace
1O ttl.m(1.O kgf.m,7 tbt.ftl

[":::,::-'
Eecause of its compact impeller design, the fuel pump is installed inside the fueltank, thereby saving space
ng the fuel line system.
FUEL PUMP
FUEL FILTER
FUEL PUMP BRACKET
FUEL PUMP CROSS SECTION lsido vi6rvl
IMPELLERS
CHECK VALVEPUMP CASING
The fuel oumo consists of a DC motor, a circumference flow pump, a relief valve for ptotecting the fuel lir
a check valve for retaining residual pressure, an inlet port, and a discharge port. The fuel pump assembly
the impellers (driven by the motor), the fuel pump casing {which forms the pumping chsmber), and the fuel p
OPERATION(1 ) When the engine is started. the PGi/t-Fl main relay actuates the fuel pump, and the motor turns togeth
impellers.
Differential pressure is generated by the numerous grooves around the impellers.
(2) Fuel entering the inlet porr flows inside the motor from the pumping chambe. and is forced through th
port via the check valve.
lf tuel flow is obstructed at the discharge side of the tuel line, the relief valve will open to bypass the
inlet port and prevent excessive fuel pressure.
(3) When the engine stops, the tuel pump stops automatically. However, a check valve closes by gravity t
residual pressure in the line, helping the engine to aestan more easily.
and simplify-
N lTop vi6w)
PORT
GROOVES
fuel line systems,
embly consists of
fuel pump cover.
together with the
rgh the discha.ge
ss the fuel to the
avitv to retain the
(cont'd)
PUMP COVER
FUEL PUMP ASSEMBLY CROSS SECTION
D|SCHARGE FORT ^ . tNLEr P
IMPELLER
11-109

Fuel Supply System
Fuel Pump (cont'dl
Tc.ting
@E o" not smoko during tho tesr. Koop openflrmo away fiom your work area.
lf you susp€ct a problem with the tuel pump, check thatthe lusl pump actually runs; when it is ON, you will hearsome noise if you hold your ear to the luel lill oon withthe fuel fill cap remov6d. The fuel pumD should run fortwo seconds, when ignition switch is first turned on. llthe fuel pump does not make noiss, check as tollows;
1. Removo the rear seat (see section 2O).
-'2. Remove the access panel.
3. Disconnect the 2P connector from the fuel pump.
CAUTION: 86 lure to tum th6 ignition switch OFFbotor6 disconnoctlng th€ wilos,
4. Connect the BLK|yEL @ wire 8nd YEL/GRN @ wirewith a iumpe. wire 8t the PGM-FI main relav con-
nectot.
l.t, .--/ re -Fl. . MAll{ RELAY
BL&YELJumper
Check that battery voltage is available at the tuel
pump connector when the ignition switch is turned
ON (positive probe to the YEL/GRN wire, negativeprobe to ths BLK/WHT wire).
ACCESSPANEL
side
YEL/GRN
a lf battery voltage is available, replace the fuel
pump.
a It there is no voltage, check the tusl pump ground
and wire harness {see page I 1-1 l2).
11-110
Roplacomont
@ oo not smoks whilo worklng on fuel syr-
tem. Kaop opon llamos away from your wolk araa.
1. Remove the rear ssats {soe section 2O).
2. Remove the access oanel.
3. Disconnect the 2P connector from the fuel pump.
4. Remove the fuel pump mounting nuts.
5. Remove the fuel pump trom the luel tank.
6. Install a new washer on the banio bolt, then install
Darts in the revers€ order of removal.
6 N.mlO.6 kgl.m,.4 tbt.ftl
27 .m(2.4 kgt.m,21 tbt.ftl

PGM-Fl Main Relay
Doscription
The PGM-Fl main relav actuallv contains two individual
rerays.
This relay is located at the lett side of the cowl.
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,
to supply power to the fuel pump.
PGM-FIMAIN RELAY
FUEL PUMP
Relay Testing
NOTE: lf the car stans and continues to r
Fl main relay is OK.
1. Remove the PGM-Fl main relay.
2. Attach the battery positive terminalto
minal and the battery negative termir
1 terminal of the PGM-FI main relay. T
continuity between the No. 5 terminal
minal of the PGM-FI main relay.
a lf there is continuity, go on 10 ste
a lt there is no continuity, replace the
relay and retest.
To lGN. I
To GROUND
To ST. SWITCH
To ECM {47}
Attach the battery positive terminalto
minal and the battery negative termil
3 terminal of rhe PGM-Fl main .elav. Tl
there is continuity between the No. ;
No.6 terminal of the PGM-Fl main re
a lf there is continuity, go on to st€
a lf there is no continuity, replace th€
relay and retest.
Anach the battery positive terminalto
minal and the battery negative termil
1 terminalof the PGM-Fl main relay, Tl
there is continuity between the No. :
No. 4 te.minal of the PGM-Fl main r
a It there is continuitv, the PGM-FI mi
a lf there is no continuity, replace th(
relav and retest.
No.2
run, the PGM-
nalto the No. 2 ter-
terminal to the No.
lay. Then check for
minal and No. 4 ter-
to step 3.
ce the PGM-Fl main
8Ar C)
ECM {425, 81)
J To FUEL PUMP
inalto the No. 5 ter-
terminsl to the No.
ay. Then check that
No. 7 terminal and
ain relay.
to step 4.
ce the PGM-Fl main
inal to the No. 6 ter-
terminal to the No.
ay, Then check that
No. 5 terminal and
nain relay.
-Flmain relay is OK.
ce the PGM-Fl main
(cont'd)
11-111