1994 HONDA INTEGRA intake manifold

ldle Control System
Fast ldle Thermo Valve
DEscliptlon
To prevent erratic running when the engine is warming
up, it is n€cessary to raise the idle speed. The fast idle
thermo valve is controlled by a thermowax plunger, When
the engine is cold. the engine coolant su.rounding the
thermowax contracts the plunger, allowing additional air
to be bypassed into the intake manifold so that the en-
gine idlss taster. When the engine reaches operating tem-
peratur€, the valve closss, reducing the amount of air
bypassing into the manifold.
FAST IDLE THERMOVALVE
AIN EYPASS VALVE
Inspaction
NOTE: The tast idle thermo valve is factory adiustsd;
it should not be disassombl€d.
1. Remove the intake air duct from the throttlg body.
2. Stan the engine.
3. Put your finger over ths lower port in throttle body
and make sure that there is 8ir flow with tho engine
cold (engine coolant temperatute below 86oF,
300c).
a lf not,
retest.
leplace the fast idle thermo valvs and
4.
o-Rr{GsReplace
llo kgf.m, 7 lbt.trl
Start the engine. Hold the sngine at 3.0OO rpm with
no load (A/T in I or @ position, M/T in neutral]
until the radiator fan comes on, then let it idl6.
Check thst valve is completely closed. lt not, air suc-
tion can be telt at the lower Don in the throttle body,
a It any suction is felt, the valve is leaking Check
engine coolant level and for air in tho engine
coolant system (see section 1O). ll OK, rsplace
the fast idle thermo valve and rechock.
11-94

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

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

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

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
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.