Page 297 of 1413

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
Page 309 of 1413

lntake Air System
Throttle Body
Description
The throttle body is ot the single-barrel side-draft 1ype.
The lower portion of the throttle valve is heated by en-gine coolant from the cylinder head. The idle adjusting
screw which increases/dec.eases bvDass air and the
Evaporative Emission (EVAP) Control Canister port are
located on the top of the throttle body.
IOLE AOJUSTING
THROTTLESTOP SCREW(Non-adiustsb16l
11-120
Insoection
CAUTION: Do not adiust the thlottle stop screw. lt ispreset at the lactory.
1. Start the engine. Hold the engine at 3,OOO rpm with
no load (A/T in S or E position, M/T in neutral) until
the radiator fan comes on, then let it idle.
2. Disconnect the vacuum hose (to the EVAP control
canister) from the top of the throttle body; connect
a vacuum, gauge to the throttle body.
VACUUM PUMPGAUGEA973X-O41-XXXXX
5.
3. Allow the engine to idle and check that the gauge
indicates no vacuum.
a li there is vacuum, check the throttle cable (see
page 1 1-'l 18, 119).
Check that vacuum is indicated on the gauge when
the throttle is opened slightly from idle.
a lf the gauge indicates no vacuum, check the throt-
tle body port. lf the throttle body port is clogged.
clean it with carburetor cleaner.
Stop the engine and check that the throttle cable
operates smoothly without binding or sticking.
a lf there are any abnormalities in the above steps,
check for:
- Excessive wear or Dlav in the throttle valve shaft.
Sticky or binding throttle lever at full close po-
srtron.
Clearance between throttle stop screw and throt-
tle lever at tull close Dosition.
Page 313 of 1413
Intake
Intake
Air
Air
System
Bypass (lAB) ControlSystem tBl8C1 enginel (cont'dl
Troublcahooting
VACUUII PUMP/GAUG€A973X-041-XXXXX
fromwiro haanasid€
PI{K/BLU I-I
YEI/aLK l+l
tA8 COI{TROLDIAPHRAGM
Insp€ction of IAB Conltol Sytt.m
Start engino and allow to idle.
R€move # 13 vacuum hose tromthe IAB control diaph.agm andconnect vacuum gauge to thehose.
R€move # 12 vacuum hose fromth€ IAB vacuum tank, then checktor vaccum at the IAB vacuumtank.
Rcplir lh. block.g. otvacuufi laak boiwaaotha IAB vacuum tanklnd th. intlk m!ni-fold.
Disconnect the 2P conn€ctor lromthe IAB control solenoid valve.
Measure voltage betweenYEL/BLK (+l torminal andPNK/8LU l-) terminsl.
ls thoro battery voltage?
Measure voltage b€twee nBLK^|/EL (+) torminal and bodyground.
IAB CONTBOLSOLENOID VALVE
Page 314 of 1413

(From page 1 1-124)
Raise engine speed to above6,000 rpm.
Disconnect the 2P connector tromthe IAB control solenoid valve.
Turn the ignition switch OFF.
Check for continuity to ground onthe PNK/BLU wire.
Ropair short to g.ound
at PNK/BLU wiro bo-two6n ECM {A17) andtho 2P connector.
ls there continuity to ground?
Substituto a known-good ECMand racheck. It symptom goos
swsy, roplace tho original ECM.
{From pago 1 1-124}
Repsir op6n in YEL/BLKwiro botwoon tho 2Pconnector and FGM-FImain relaY.
ls there battery voltage?
Turn the ignition swirch OFF.
Connect lhe test harness betweenthe ECM and connectors lseepage 11-37).
Turn the ignition switch ON andconnect a lumper wke betweenECM (A17) terminal and ECM
{A26) terminal.
Ropaiiopon inP K/BLUwiao botwoen ECM
lAl7l and tho 2P con-nectot.
Ooes the solenoid valve clickwhen the jumper is con-nected?
Sub3titute a known-good ECMand rechock. lf symptom/indica-tion goos away, r6place tho origi-nal ECM.
Check lor vacuum at #'l3 vacu-um hose.
IAB control syst6m is OK.
11-125
Page 315 of 1413
a
Intake Air System
Intake Air Bypass (lABl Control Valve IB18C1 enginel
Trlting
GAUTIOI{; Do not rdlust lho IAB control valvo tull-close screw. lt is prosot at th. t.ctoty.
1. Chsck the IAB control valve shsft for binding or sticking.
2. Check th6 IAB control valve for smooth movement.
3. With the engine at idle, check that @ot the IAB control valve is in close contact with the stoppsr when vacuum
hose is disconnected.
With th€ ongine at idl6, check that @of the IAB control valve is in close contact with the full-closo acrew whsn
the vacuum hose is connectad.
a lf 8ny fault is lound, clean the linkage and shatts with carburetor claaner'
- lf the oroblam still exists after cleaning, disassemble the intake manifold and check the IAB valvE body sss8mbly.
11-126
Page 323 of 1413
Emission Control System
Positive Crankcase Ventilation (PCVI System
Description
The Positive Crankcase Ventilation (PCV) system is
designed to prevent blow-by gas {rom escaping to the
atmosphsre. The PCV valve contains a spring-loadsd
plunger. When the Bngine starts, the plunger in the PCV
valve is lifted in proportion to intake manifold vacuum
and the blow-by gas is drawn directly into th€ intak€
manifold.
FCV VALVE
.F: ILOW-BY VAFORer FRESH AIR
11-134
Insp€cdon
1. Check th€ PCV hos6s and connections tor lsaks and
clogging.
At idle, mak6 sur€ th6fe is a clicking sound from th6
PCV valve when the hose between rcV valve and
intake manifold in lightly pinched with your fingors
or oli€rs.
a lf thera is no clicking sound, ch6ck the PCV valve
grommet for cracks or damage. ll the grommet
is OK, reolace the PCV valve and recheck.
2.
SREATHER
Gontly pinch hero.
Page 324 of 1413
A.
Evaporative Emission (EVAPI Controls
Da.cdptlon
Thg avaporstive omission controls are designed to minimize the smount of fusl vapor escaping to the atmosphero. The
system conaists ot the following compon€nts:
Evlporttly. Emlttbn (EVAPI Control Caniltot
An EVAP control canistor is used lor the temporary storage ot fuel vapor until the fuel vapor can be purged lrom
th€ EVAP control canister into the engin€ and burned.
vlpor hr]gG Cmt]ol Syst m
€VAp control canistgr puroing is accomplished by drawing fresh air through tho EVAP control canister and into a
pon on th6 throttl€ body. Th€ purging vacuum is controllsd by the EVAP purge control diaphragm valve end the
EVAP purge control solenoid valve.
C. Ft|.l Tmk Vlpor Control Systom
When fuel vapor prassure in the fuel tank is higher than the set v8lue of the EVAP two way v8lv6, th€ valve opens
and regulates the flow ol fuel vapor to the EVAP control canister.
(cont'd)
11-135
Page 326 of 1413
#7 VACUUM HOSE
Troublclhooting
VACUUM PUMP/GAUGEA973X-O41-XXXXX
EVAP PTJBGE COI{TROLDIAPHRAGM VALVE
EVAPPUBGE CONTROL
Bl8Bl .noin.:YEL/BLK I+I
(-t
wirg aide
--\
EVAPR'RGE COI{TROLSOLENOID VALVE
(cont'd)
VALVE
YEL/BLK (+I
Disconn€ct #7 vacuum hose
trom the EVAP putgo control di'
aph.agm valve lon the EVAPcon-
t.ol canistor) and connoct a
vacuum gauge to tho hose.
Stsrt the €ngine and allow it toidls.NOTE: Engine coolant tempera-
ture must be b€low 163oF (73ocl
Oisconnect the 2P connegtor trom
the EVAP purge control solenoid
Mea suro voltago betw€enYEL/BLK {+) terminsl 6nd RED
l-) terminal.
Inapact vacuum hoa€ror.ring.l| OK, toolrc. EVAPpurgo conttol solenoidls ther6 battery voltage?
Moasule voltage botweenYEL/BLK {+) terminal bodYground.
(To pa96 1 1- 138)
(To page 1 'l -139)
11-137