1995 ACURA TL engine

Throttle Cable

Inspection/Adjustment

1.

2.

3.
Start the engine. Hold the engine at 3,000 rpm with

no load (transmission in or position) until the

radiator fan comes on, then let it idle.

Check that the throttle cable operates smoothly with

no binding or sticking. Repair as necessary.

Check cable free play at the throttle linkage. Cable

deflection should be 10 - 12 mm (0.39 - 0.47 in.)

CABLE

BRACKET.
ADJUSTING

NUT

LOCKNUT

DEFLECTION

10-12
mm

(0.39
-
0.47 in.)

4. If deflection is not within specs, loosen the locknut,

turn the adjusting nut until the deflection is as spec-

ified, then retighten the locknut.

5. With the cable properly adjusted, check the throttle

valve to be sure it opens fully when you push the

accelerator pedal to the floor. Also check the throttle

valve to be sure it returns to the idle position whenev-

er you release the accelerator pedal.
Installation

1. Fully open the throttle valve, then install the throttle

cable in the throttle linkage and install the cable

housing in the cable bracket.

CABLE

BRACKET

THROTTLE

LINKAGE
ADJUSTING

NUT

LOCKNUT

INNER CABLE

2. Start the engine. Hold the engine at 3,000 rpm with

no load (transmission in or position) until the

radiator fan comes on, then let it idle.

3. Hold the cable sheath, removing all slack from the

cable.

4. Turn the adjusting nut until it is 3 mm (0.12 in.) away

from the cable bracket.

CABLE

BRACKET

ADJUSTING NUT

LOCKNUT

9.8 N-m

(1.0 kgf-m,

7.2 Ibf-ft)
3 mm

(0.12 in.)

5.
Tighten the locknut. The cable deflection should now

be 10 - 12 mm (0.39 - 0.47 in.). If not, see inspection/

adjustment.ProCarManuals.com

Intake Ai r Syste m
Throttl e Bod y
Descriptio n
The throttl e bod y i s a single-barre l side-draf t type . Th e
lowe r portio n o f th e throttl e valv e i s heate d b y engin e
coolan t fro m th e cylinde r head . Th e idl e adjustin g screw ,
whic h increases/decrease s bypas s air , an d th e Evaporativ e
Emissio n (EVAP ) Contro l Caniste r por t ar e locate d o n th e
to p o f th e throttl e bod y ('9 5 - '9 6 model s only) .
THROTTL E
POSITIO N
(TP)SENSO R IDL
E ADJUSTIN G
SCREW
THROTTL EVALVE
THROTTL ESTOPSCRE W(non-adjustable )
Inspection
1.
2 .
Disconnec t th e vacuu m hos e fro m th e to p of the
throttl e body ; connec t a vacuu m gaug e t o th e throt -
tle body. *
Start th e engine . Hol d th e engin e a t 3,00 0 rp m wit h
no loa d (transmissio n in o r position ) unti l th e
radiato r fa n come s on , the n le t i t idle. *
VACUU MPUMP/GAUGE , 0-3 0 in.H gA973 X - 04 1 - XXXX X
3. Allo w th e engin e t o idle , an d chec k tha t th e gaug e
indicate s n o vacuum. *
I f ther e i s vacuum , chec k th e throttl e cabl e (se e
pag e 11-137 ).
4 . Chec k tha t vacuu m is indicate d o n th e gaug e whe n
the throttl e is opene d slightl y fro m idle. *
If th e gaug e indicate s n o vacuum , chec k th e throttl e
bod y port . I f th e throttl e bod y por t i s clogged , clea n i t
wit h carbureto r cleaner .
5 . Sto p th e engine , an d chec k tha t th e throttl e cabl e
operates smoothly withou t bindin g o r sticking .
If ther e ar e an y abnormalitie s chec k for :
• Excessiv e wea r o r pla y i n th e throttl e valv e shaft .
• Stick y o r bindin g throttl e leve r a t th e full y close d
position .
• Clearanc e betwee n throttl e sto p scre w an d throt -
tl e leve r a t th e full y close d position .
* : '95-9 6 model s onl y
ProCarManuals.com

Intake Air Bypass (IAB) Control System

Description

Two air intake paths are provided in the intake manifold to allow the selection of the intake path most favorable for a

given engine speed. Satisfactory power performance is achieved by closing and opening the intake Air Bypass (IAB)

valves. High torque at low rpm is achieved when the IAB valves are closed, whereas high power at high rpm is achieved

when the IAB valves are opened.

IAB CONTROL

DIAPHRAGM

From No. 4 ECU (ECM)

('95-96 models: 15A,

'97 - 98 models: 20A) FUSE

(In the under-dash

fuse/relay box)

VARIOUS

SENSORS

IAB

CONTROL

SOLENOID

VALVE

IAB VACUUM TANK

IAB CONTROL SOLENOID VALVE OFF

ENGINE RPM IS ABOVE 4,800 rpmProCarManuals.com

Intake Ai r Syste m Emissio
n Contro l Syste m
Intake Ai r Bypas s (IAB ) Contro l
Syste m (cont'd )
Intake Ai r Bypas s (IAB ) Contro l Valv e Testin g
1. Chec k th e IA B contro l valv e shaf t fo r bindin g o r stick -
ing.
2. Chec k th e IA B contro l valv e fo r smoot h movement .
3. Chec k tha t o f th e IA B contro l valv e is i n clos e con -
tac t wit h th e stoppe r whe n th e vacuu m hos e i s dis -
connecte d fro m th e IA B contro l diaphragm .
IAB CONTRO L VALV ESTOPPE R
4.Chec k tha t o f th e IA B contro l valv e is in clos e con -
tac t wit h th e full-clos e scre w whe n yo u appl y 5 1 kP a
(38 0 mmHg , 1 5 inHg ) o f vacuu m to th e IA B contro l
diaphragm .
FULL-CLOS ESCREW(Do no t adjust. )
If an y faul t i s found , clea n th e linkag e an d shaft s wit h
carbureto r cleaner . I f th e proble m stil l exist s afte r clean -
ing , disassembl e th e intak e manifol d an d chec k th e IA B
valv e bod y assembl y (se e sectio n 9 ).
Syste m Descriptio n
The emissio n contro l syste m include s a War m U p Thre e
Wa y Catalyti c Converte r (W U TWC) , a Thre e Wa y Catalyti c
Converte r (TWC) , Exhaus t Ga s Recirculatio n (EGR ) system ,
Positiv e Crankcas e Ventilatio n (PCV ) syste m an d
Evaporativ e Emissio n (EVAP ) Contro l system . Th e emis -
sio n contro l syste m is designe d t o mee t federa l an d stat e
emissio n standards .
Tailpipe Emissio n
Inspectio n
Do no t smok e durin g thi s procedure . Kee p
an y ope n flam e awa y fro m you r wor k area .
1 . Star t th e engine . Hol d th e engin e a t 3,00 0 rp m wit h
no loa d (transmissio n i n o r position ) unti l th e
radiato r fa n come s on , the n le t i t idle .
2 . Connec t a tachometer .
3 . Chec k an d adjus t th e idl e speed , i f necessar y (se e
pag e 11-117 ).
4 . War m u p an d calibrat e th e C O mete r accordin g to th e
mete r manufacturer' s instructions .
5 . Chec k idl e C O wit h th e headlights , heate r blower ,
rea r windo w defogger , coolin g fan , an d ai r condition -
er off .
NOTE : (Canada ) Pul l th e parkin g brak e leve r up .
Star t th e engine , the n chec k tha t th e headlight s ar e
off.
CO mete r shoul d indicat e 0.1 % maximum .
ProCarManuals.com

Positive Crankcase Ventilation (PCV) System

Description

The Positive Crankcase Ventilation (PCV) system is

designed to prevent blow-by gas from escaping to the

atmosphere. The PCV valve contains a spring-loaded

plunger. When the engine starts, the plunger in the PCV

valve is lifted in proportion to intake manifold vacuum and

the blow-by gas is drawn directly into the intake manifold.

BREATHER

HOSE

PCV VALVE
BLOW-BY VAPOR

FRESH AIR
Inspection

1. Check the PCV hoses and connections for leaks and

clogging.

PCV HOSE

PCV VALVE

2.
BREATHER

PIPE

At idle, make sure there is a clicking sound from the

PCV valve when the hose between PCV valve and

intake manifold in lightly pinched with your fingers

or pliers.

Gently pinch here

If there is no clicking sound, check the PCV valve

grommet for cracks or damage. If the grommet is

OK, replace the PCV valve and recheck.
INTAKE

MANIFOLDProCarManuals.com

Emission Control System

Evaporative Emission (EVAP) Controls

Description

The evaporative emission controls are designed to minimize the amount of fuel vapor escaping to the atmosphere. The

system consists of the following components:

A. Evaporative Emission (EVAP) Control Canister

An EVAP control canister is used for the temporary storage of fuel vapor until the fuel vapor can be purged from the

EVAP control canister into the engine and burned.

B. Vapor Purge Control System

EVAP control canister purging is accomplished by drawing fresh air through the EVAP control canister and into a port

on the throttle body. The purging vacuum is controlled by the EVAP purge control solenoid valve.

'95 - 96 models:

EVAP PURGE CONTROL SOLENOID VALVE OFF AFTER

STARTING ENGINE

'97 - 98 models:

EVAP PURGE CONTROL SOLENOID VALVE DUTY CON-

TROLLED AFTER STARTING ENGINE

C. Fuel Tank Vapor Control System

When fuel vapor pressure in the fuel tank is higher than the set value of the EVAP two way valve, the valve opens and

regulates the flow of fuel vapor to the EVAP control canister.
ENGINE COOLANT TEMPERATURE ABOVE 167°F (75°C)

ENGINE COOLANT TEMPERATURE ABOVE 158°F (70°C)ProCarManuals.com

Description

The automatic transmission is a combination of a 3-element torque converter and a dual-shaft electronically controlled

automatic transmission which provides 4 speeds forward and 1 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, assembled in a single unit.

They are connected to the engine crankshaft so they turn together as a unit as the engine turns.

Around the outside of the drive plate is a ring gear which meshes with the starter pinion when the engine is being started.

The entire torque converter assembly serves as a flywheel while transmitting power to the transmission mainshaft.

The transmission has two parallel shafts: the mainshaft and the countershaft. The mainshaft is in line with the engine

crankshaft.

The mainshaft includes the 1st, 2nd and 4th clutches, and gears for 4th, 2nd, 1st and reverse (3rd gear is integral with the

mainshaft, while the reverse gear is integral with 4th gear).

The countershaft includes the 3rd, and 1st-hold clutches, and gears for 3rd, 4th, 1st, 2nd, reverse, and parking. The sec-

ondary drive gear is integrated with the countershaft.

The gears on the mainshaft are in constant mesh with those on the countershaft.

When certain combinations of gears in the transmission are engaged by clutches, power is transmitted from the mainshaft

to the countershaft to provide and positions.

Electronic Control

The electronic control system consists of the Transmission Control Module (TCM), sensors, a linear solenoid and four

solenoid valves. Shifting and lock-up are electronically controlled for comfortable driving under all conditions.

The TCM is located below the dashboard, behind the glove box on the passenger's side.

Hydraulic Control

The lower valve body assembly includes the main valve body, the servo body and the shift control solenoid valves. They

are bolted on the lower part of the transmission housing.

Other valve bodies, the regulator valve body, the ATF pump body, the 2nd accumulator body, and the throttle valve body,

are bolted to the torque converter housing.

The main valve body contains the manual valve, the 1 - 2 shift valve, the 2 - 3 shift valve, the 3 - 4 shift valve, the 4th kick-

down valve, the 2 - 3 orifice control valve, the 3 - 4 orifice control valve, the 4th exhaust valve, the servo control valve,

and the main orifice control valve.

The servo body contains the servo valve, 3rd and 4th accumulator pistons.

The regulator valve body contains the regulator valve, the lock-up shift valve, and the cooler relief valve.

Fluid from the regulator passes through the manual valve to the various control valves.

The throttle valve body includes the throttle valve which is bolted onto the 2nd accumulator body. The 2nd accumulator

piston is assembled in the 2nd accumulator body.

The linear solenoid is joined with the throttle valve body.

The ATF pump body contains the modulator valve, the lock-up control valve, the lock-up timing valve, and the relief valve.

The torque converter check valve is located in the torque converter housing under the ATF pump body.

The 1st and 1st-hold accumulator pistons are assembled in the rear cover.

The clutches receive fluid from their respective feed pipes or internal hydraulic circuit.

Shift Control Mechanism

Input from various sensors located throughout the vehicle determines which shift control solenoid valve the TCM will acti-

vate. 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 in position in 3rd, pressurized fluid is drained from the back of the torque con-

verter through a fluid passage, causing the lock-up piston to be held against the torque converter cover. As this takes place,

the mainshaft rotates at the same speed as the engine crankshaft. Together with hydraulic control, the TCM optimizes the

timing of 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. When lock-up control solenoid valves A and B activate, the modulator pressure changes.

The lock-up control solenoid valves A and B are mounted on the torque converter housing, and are controlled by the TCM.ProCarManuals.com

Position

The power flow when decelerating is as follows:

1. Rolling resistance from the road surface goes through the front wheels to the secondary drive gear, then to the coun-

tershaft 1st gear via the 1st-hold clutch which is applied during deceleration.

2. The one-way clutch disengages at this time because the application of torque is reversed.

3. The counterforce conveyed to the countershaft 1st gear turns the mainshaft 1st gear. At this time, since hydraulic

pressure is also applied to the 1st clutch, counterforce is also transmitted to the mainshaft. As a result, engine braking

can be obtained with 1st gear.

TORQUE CONVERTER

MAINSHAFT 1ST GEAR

1ST CLUTCH

MAINSHAFT

SECONDARY

DRIVE GEAR
COUNTERSHAFT

1ST-HOLD

CLUTCH

COUNTERSHAFT

1ST GEAR

SECONDARY DRIVEN GEARProCarManuals.com