1994 HONDA INTEGRA engine

Intake Air Bypass (lABl Control System tBl8C1 enginel
Osscription
Two air intake paths are provided in the intake manifold to allow the selection of the intak€ path most favc
given engine speed.
Satisfactory power peformanc€ is achieved by closing and opening the intake air bypass (lAB) control valve!
que at low RPM is acheived when the valves are closed, whereas high power at high RPM is achieved by when
8re oDeneo.
IAB CONTROLVALVES
To PGM-FIMAIN RELi
IABCHECK VALVE
t favorabl€ for a
vslves. High tor-
when the valves
RELAY
(cont'dl
11-123

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

(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

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

Intake Air System
Intake Manifold IB18B1 enginel
Disassembly:
{ uuu
24 N.m12.4 kgf.m,t7 tbt.ftl23 N'm(2.3 kgt.m,17 tbf.ftl
11-128

Emission Control System
SystemDescription
The emission control system includes a Three Way Cata-
lytic Convener (TWC), Positive Crankcase Ventilation(PCV) system and Evaporstive Emission {EVAP) Contfol
syst€m. The emission control system is designed to meet
federsl and stats emission standards.
Tailpipe Emission
Inspection
f!fifil oo nor amoro ou]rng rnr! Foacqurr. ^!op
any open flame away from yout wotk atca.
Start the engine. Hold the engine at 3,OOO rpm with
no load (A/T in @ or@ position, M/T in neutral) until
the radiator fan comes on, then let it idle,
Connect a tachometer.
Check and adiust the idle speed, if necessary (sss
page 1 1-95).
Warm up and calibrate the CO meter according to
the meter manutacturer's inst.uctions.
Check idle CO with the headlights, hester blower,
rear window defogger, cooling fan, and air condition-
er otf.
NOTE: (Canada) Pull the parking br8ke lever up.
Stan the engine, then check that the headlights are
off.
CO meter should indicate 0.1 maximum.
11-130

Three Way Gatalytic Converter ITWC)
Dr!criplion
Th6 Three Way Cstalytic Converter (TWC) is used to convert hydrocarbons (HCl, carbon monoxide (CO), and oxides
ot nitrogen {NOx) in the exhaust gas, to carbon dioxide (COr}, dinitrogen (N2l and water vapo..
The illustration shows the TWC tor the 818C1 engine.
FBONT OFVEHICLE
THREE WAYCATALYSTS
11-131

818Cl engine:
HEAT SHIELO
r{
THREE WAYCATALYTICCOI{VEBTEB {TWCIR€moval/installation. sso s€ction 9Inspoct housing tor cracks orothor damage.Inspect elemont for cloggingby looking through the inside.
HEAT SHIELD
11-133