1994 HONDA INTEGRA idle air control

Intake Air System
System Troubleshooting Guide
NOTE: Across 6ach row in the chart, the sub-systems that could be sources of a symtom are ranked in the order they
should be inspected st8rting with O. Find the symptom in the left column, read across to the most likely source, then
ret€r to the page listod at the top of that column. tf inspection shows the system is OK, try the next system @, etc.
181881 onglnol
't 1-11711-118
WHEN COLD FAST IOLE OUT OF SPEC
WHEN WARM IDLE SPEED TOO HIGH
lB18Cl cngin.l
PAGE I sue-svsreu
_\.-..\
sYMPToM \---...-
THROTTLE
CABLE
THROTTLE
BODY
INTAKE AIR
BYPASS (IAB)
CONTROL
AIR CLEANER
AND INTAKE
AIR DUCT
111191't -12011-1241l117
WHEN COLD FAST IDLE OUT OF SPECo
WHEN WARM IDLE SPEED TOO HIGHoo
LOSS OF POWERo@@
11-115

Intake Air System
System Description
The system supplies air for allengine needs. lt consists of the intake air pipe, Air Cleaner (ACL), intake air duct, Throttle
Body (TB), ldle Air Control {lAC) Valve, tast idle thermo valve, and intake manifold.
A resonator in the intake air pipe provides additional silencing as air is drawn into the system.
nacot{TRoLSOLENOIDVALVE
To
ffi -------------+ i'"ii'i''RELAY
VARIOUSSENSORS
IABCONTROLDIAPHRAGMVALVE
-BLK--L EI{GINE- cooLnnt
tFASTIDLETHERMOVALVE
U
INTAKEAIR PIPE
INTAKEAIRDUCT
11-116

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.

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

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

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

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.

(From page 1 1-137)
lTo page 1 1-'l39)
Start the engine. Hold the engineat 3,OOO rom with no load lA/T in
E orE position, M/T in neutrsl)unlil lhe radiator tan comes on.then let it idle.
Check lor vacuum at # 7 vacuumhose alter starting the engine.
Oisconnect the 2P connoctor fromthe EVAP purge control solenoid
Intpoct vacuum hoaarcuting.It OK, reolrco tr|c EVAP
Purge contlol lolanoid
ls there manifold vacuum?
Inrpoct for a short i|t RED wire bo-lwoen ECM {A2Ol and th6 con-noclor.ll wiro la OK, substituto a known-good ECM 6nd .echock. lf symp-tom goes away, loplace tho origi-nal ECM.
Ropair opon in YEL/BLKwirc b.tw..n EVAPpurgo control rolanoidvrlvo and th. xiM-Flmlin r6lay.
ls there baftery voltage?
Inspoct RED wirc for 6n opon totrody g.ound botween ECM lA20)and th6 conn6ctor.It wir. b OK, substiluto a known-good ECM and rochock, It sym-ptom 9o6s away, roplaco thooriginal ECM,
Emission Gontrol System
Evaporative Emission (EVAP) Gontrols (cont'd)
{From page 11-137}
11-138