1994 HONDA INTEGRA Idle

ldle Control System
ldle Air Control (lACl Valve
lt6l- -l lf l- The Maltunction Indicator Lamp (MlL) indicates Diagnostic Trouble Code {DTC} 14: A problem in
' '- the ldle Air Control llAC) Valve circuit.
The IAC Valve changes the amount of air bypasEing the throttle body in respons€ to a current signal from the ECM in
order to maintain the proper idle speed.
ffi: r;611/ | /--T-\
- The MIL h.3 been report don,- With tho SCS shon connoctolconnoctod (soo pago 'l 'l -341,
cod6 14 is indicatod.
Do the ECM Reset Procedure (seepage 11-35).
With the engine running snd theaccelerator pedal releas€d, dis-conn€ct th€ 2P connector frorttho IAC valvo.
ls the MIL on and does it indicatecode 14?
htarmitlaot frlu]., aya-t.m i. OK !t thir tlft.
ll.rl drlv. mly ba nac-aaaaryl.Chack tor Doo. conn€c-tlonr oi loora wirca atC3O5 (loc.t.d .t |.ftlhock tow.tl, C424,Cl tB (lAC v.lvol .ndECM.
Disconnect the 2P connector fromthe IAC valve.
Sub.iituto . known{ood IACvdva lnd iotolt.
{To page 11-83}
11-82

ldle Control System
Alternator (ALTI FR Signal
This signals the ECM when the Alternator (ALT) as charging.
D9 l+)
Inspection ot ALT FR Sign.l.
Connect the tost harness betweenthe ECM and connectors. Discon-nect "D" connector from themain wire harnoss only, not theECM lsee page 11-37).
Turn the ignition switch ON.
Measure voltage between D9 (+ )terminal and A26 {-}terminal.
Sub{inno s known-good ECMand redrack. It pro.ctibod volt gola now availablg, ropllco tha orlg-inal ECM.
ls there approx. 5 V?
Turn the ignition switch OFF.
Reconnect "D" connector to themain wire harness,
Start tho engino. Hold the engine
!L3,099 rpm with no load (A/T in
LN] or El position, M/T in neutral)until the radiator tan comes on,rhen let it idle.
Measuro voltage between Dg (fl
terminal and 426 (- I terminal.
Does the voltage decreasewhen headlights and .eardelogger are turned on?Turn ths ignition switch OFF.
ALT FR rignal is OK.
o oo oo o ooooo
ooooooooooo
Voh.go?
ooooooooooo
ooooooooooo
1 1-86
(To page 1 1-87)
=-

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

- ldle Speed Setting
Inspoction/Adiustment
NOTE:
a When the idle speed set, check the following items:
- The MIL has not been reported on.- lgnition timing- Spark plugs- Air cleaner- PCV svstem
a (Canada) Pullthe parking brake lever up. Stan the en-
gine, then check that the headlights are off.
1 Start the engine. Hold the engine at 3,000 rpm with
no load (A/T in S or @ position, M/T in neutral)
until the radiator tan comes on, then let it idle.
2. Connect a tachometer.
3. Disconnect the 2P connectot trom the ldle Air Con-
trol {lAC) valve.
Start the engine with the sccelerator pedal slightly
depressed. Stabilize the rpm at 1 ,OOO, then slowly
release the pedal until the engine idles.
Check idling in no-load conditions: headlights, blower
fan, rear defogger, radiator fan, and ai. conditioner
are not operatrng.
ldl€ spood should bo;
81881 ongino:
MlT48O ! 50 rym
An48O I 50 rpm
lin@or@oosition)
818C7 engine:48O ! 50 rym
Adjust the idle speed, if necessary, by turnmg the
idle adiusting screw.
NOTE: After adiust the idle speed in this step, check
the ignition timing (see section 231.
lf it is out ot spec. go back to step 4.
4.
e
Turn the ignition switch OFF.
Reconnect the 2P connector on the IAC valve, then
remove the BACK UP (7.5 A) fuse in the under-hood
tuse/relav box for 1O seconds to reset the ECM.
Restart 8nd idle the engine with no-load conditions
for one minute, then check the idle speed.
NOTE: (Canada) Pull the parking brake lever up.
Start the engine, then check that the headlights ate
off.
ldlo speed should be;
81881 ongino:
MTf75O ! 50 rpm
AIT75O t 50 rpm
(in[]or@positionl
818C1 engine: 750 1 50 rpm
(cont'd)
11-95

ldle Control System
ldle Speed Setting (cont'd)
10.
9. ldle the engine for one minute with headlights {Low}
ON and check the idle sDeed.
ldla sp6od should bo;
81881 engine:
M/T750 i 50 rpm
An75O t 50 rpm
{in $ or p] positionl
818C1 engine: 75O 1 50 rpm
Turn the headlights off.
ldle the engine for one minute with heater tan switch
at Hl and air conditioner on, then check the idle
speeo.
ldls spood should bo;
81881 ongino:
M/T82O 1 50 rpm
AN840 1 50 rpm(in [N] or lll position)
818C1 engino: 85O t 50 nm
NOTE: lf the idle speed is not within specitication,
see System Troubleshooting Guide on page 1 1-78.
11-96

Fuel Supply System
System Troubleshooting Guide
NOTE: Across each row in the chart, the sub-systems that could be sources of a symptom ara tanked in tho order they
should be inspected starting with O. Find the symptom in the left column, read across to the most liksly source, then
refer to the page listed at the top of that column. lf inspection shows the system is OK, try the next most liksly system
@, etc.
PAGE
SYI\4 PTOM
FUEL
LINES
FUEL
INJECTOR
FUEL
PRESSURE
REGULATOR
FUEL
FILTER
FUEL
PUMP
PGM-FI
MAIN
RELAY
CONTAM'
INATEO
FUEI
11-9811-1021 1,106l1-toa11-109t'l'nl
ENGINE WON'T START@o@
DIFFICULT TO START
ENGINE WHEN COLD OR HOTo\4
ROUGH IDLEo@
POOR PER.
FORMANCE
MISFIRE OR
ROUGH
RUNNINGo@@
FAILS
EMtSSION@o
LOSS OF
POWER@@o
FREOUENT
STALLING
WHILE
WARMING
UPo
AFTER
WARMING
UPo
11-97

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