1994 HONDA INTEGRA roll

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

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

Transmission Assembly
Removal
Mskc aurs iack! and safoty Etands aro placod proper-
ly lsl8 saqtion 1|.
Apply parking brake tnd block rear whccl! to car
will not roll ofl stand3 and f.ll on you while wotking
undrr it.
CAUTION: Use tondcr coyar3. to avoid drmlging
plintsd 3qrfaca3,
Disconn€ct the negative {-) cable from the battery,
then the positive (+) cable.
Drain the transmission oil, then reinstall the drain
plug with a new washer (see page 13-3),
Remove the intake air duct and the air cleaner hous-
ing assembly,
AIR CITANERHOUSING
13-4
4. Disconnect the back-up light switch connoctor and
the transmission ground wir€.
5, Remove the lower radiator hose clamp trom ths
transmission hanger B.
BACK.UP LGHTsuTcH cot{t{EcToR
lnaNsMttistoNGROUND WIRE
tnaNsi ssloNHANGEB B
o.
1.
R€move the wire harness clamPs.
Disconnect the stsrt€r motor cables and the vahicla
soeed sensor (VSS) connector.
VSS OONNECTOR

The Automatic Transmission is a combination of a 3-e,ement torque convefter and triple-shaft electfonically controlled
automatic transmission which provides 4 speeds forward and 1 speed reverse. The entire unit is positioned in line with
the engine.
Torque Converter, Gears and Clutches
The torque converter consists of a pump, turbine and stator assembly in a single unit, The torque converter is connected
to the engine crankshaft so they turn together as a unit as the engine turns. Around the outside of the torque converter
is a ring gear which meshes with the starter pinion when the engine is being staned. The entire torque converter assem-
bly serves as a flywheel while transmitting power to the transmission mainshaft.
The transmission has three parallel shafts, the mainshaft. countershaft and sub-shaft. The mainshatt is in line with the
engine crankshaft.
The mainshaft includes the clutches for 1 st, and 2ndl4th, and gears for 3rd. 2nd, 4th, reverse and l st (3rd gear is in-
tegral with the mainshaft, while reverse gear is integral with the 4th gear).
The countershaft includes the 3rd clutch and gears Ior 3rd, 2nd,4th, reverse, lst and parking. Reverse and 4th gears
can be locked to the countershaft at its center, providing 4th gear or reverse, depending on which way the selector is moved.
The sub-shaft includes the lst-hold clutch and gears for 1st and 4th
The gears on the mainshait are in constant mesh with those on the countershaft and sub-shaft. When certain combina-
tions of gears in the transmission are engaged by the clutches, power is transmitted from the mainshaft to the counter-
shaft via the sub-shatt to provide @, E, tr. tr and @ position.
Electronic Control
The electronic control system consists of the Transmission Control Module {TCM), sensors, and 4 solenoid valves. Shift-
ing and lock-up are electronically controlled for comfortable driving under all conditions.
The TCM is located below the dashboard, behind the left side kick panel on the driver's side.
Hydraulic Control
The valve bodies include the main valve body, secondary valve body, regulator valve body. servo body, and lock-up valve
body throuqh the respective separator plates.
They are bolted on the torque converter housing.
The main valve body contains the manual valve, 1-2 shift valve, 2-3 shift valve, Clutch Pressure Cont.ol (CPC) valve,
4th exhaust valve, relief valve, and oil pump gears.
The secondary valve body contains the 4-3 kick-down valve,3-2 kick-down valve,2-3 orifice cont.ol valve, 3-4 shitt
valve, orifice control valve. modulator valve, and servo control valve
The regulator valve body contains the pressure regulator valve. lock-up control valve, torque converter check valve, and
cooler check valve.
The servo bodv contains the servo valve which is integrated with the reverse shift fork, throttle valve B, and accumulators.
The lock-ug valve bodv contains the lock-up shift valve and lock-up timing B valve. and is bolted on the secondary valve
body.
Fluid from the regulator passes through the manual valve to the various control valves.
Shitt Control Mochanism
Input to the TCM i.om various sensors located throughout the car determines which shift control solenoid valve should
be activated.
Activating a shift control solenoid valve changes modulator pressure, causing a shift valve to move. This pressurizes
a line to one of the clutches. engaging that clutch and its corresponding gear.
Lock-up Mechanism
In @ position. in 2nd, 3rd and 4th, and E position in 3rd, pressurized tluid can be drained from the back of the tor-
que converter through an oil passage, causing the lock-up piston to be held against the torque converter cover. As this
takes Dlace, the mainshaft rotates at the same speed as the engine crankshatt. Together with hydraulic control, the TCM
optimizes the timing ol the lock-up mechanism.
The lock-up valves control the range of lock-up according to lock-up control solenoid valves A and B, and throttle valve B
When lock-up control solenoid valves A and B activate, modulator pressure changes. Lock-up control solenoid valves
A and B are mounted on the torque converter housing, and are controlled by the TCM.
(cont'd)
14-3

L!_j Position Deceleration
The power tlow when decelerating is as follows;
1. Rolling resistance lrom the road surface goes through the tront wheels to the final drive gear, then to the sub-shaft
1st gear via the 4th gear, and lst-hold clutch which is applied during deceleration.
2. The one-way clutch becomes free at this time because torque reverses.
3. The counterforce conveyed to the countershaft 4th gear turns the sub-shaft 4th gear via the mainshaft 4th gear.
At this time, since hydraulic pressure is also applied to the 1st clutch, counterfo.ce is also transmitted to the main-
shaft. As a result, engine braking can be obtained with lst gea.-
CLUTCH
SUB-SHAFT4TH GEARSUB-SHAFT 1ST GEARTOROUE CONVENTER
FINAL DRIVE
SUB'STIAFT
lST CLUTCH
MAINSHAFT
COUNTERSHAFT
REVEFSE SELECTOR HUB
REVERSE SELECTOR
(cont'dl
4TI1 GEAB
14-11

Description
Electronic Control System
Electronic Control System
The electronic control system consists of the Transmission Control Module (TCM), sensors. and 4 solenoid valves. Shift-
ing and lock-up are elect.onically controlled for comfortable driving under all conditions.
The TCM is located below the dashboard, behind the left side kick panel on the driver's side.
Lock-up ControlSolonoid Valvo A
14-18

Description
Electronic Control System (cont'd)
. GRADE LOGIC CONTROL SYSTEM
How it works:
The TCM compares actual driving conditions with driving conditions memorized in the TCM. based on the input trom
the vehicle speed sensor, throttle position sensor, engine coolant temperature sensor, brake switch signal and select
lever position signal, to control shifting while a vehicle is ascending or descending a slope. or reducing speed.
SIGNALS DETECTED
Dliving ResistanceJudgement of Controlling Area
Engine Coolant
TemDerature Sensor
. Flat road mode. Asconding mode
(Fuzzy logic). Gradual Ascending
mode. Steep Ascending
14-20

Description
Hydraulic Control (cont'dl
Main Valvo Body
The manual valve, 1-2 shift valve, 2-3 shift valve. 4th exhaust valve. CPC valve, and relief vatve are all assembled inthe main valve body,
The primary function of this valve body is switching oil passages on and off and controlling the hydraulic pressure gotngto the hydraulic control system.
4TH EXHAUST VALVECPC VALVE
RELIEF VALVE
MANUAL VALVEMAIN VALVE BODY
S€condary Vslve Body
The secondary valve body is located on the main valve body. The 3-2 kick-down valve, 4-3 kick-down valve. 2-3 orificecontrolvalve. orifice controlvalve, 3-4 shift valve, modulator valve, and servo control valve are assembled in the secon-da.y valve body.
ORIFICE COIITROLVALVE2-3 ORIFICE CONTBOL VALVE
3.4 SHIFT VALVE
VALVE BODY
MOOULACOITTROL VALVE
1.2 SHIFT VALVE
14-26