1998 ACURA INTEGRA torque

Description
Hydraulic Flow {cont'dl
l ll or &j Position
1. lst Geal
The flow of fluid through the torque converter circuit is the same as in lll postion.
The line pressure (1) becomes line pressure (4) and it becomes the 1st clutch pressure (10). The 1st clutch pressure is
applied to the 1st clutch and 1st accumulator; consequently, the vehicle will move as the engine power is transmitted.
The line pressure (1) becomes the modulator pressure (6) by the modulator valve and travels to 1-2 and 3-4 shift
valves. The l-2 shift valve is moved to the right side because the shift control solenoid valve A is turned OFF and B is
turned ON by the TCM. This valve stops 2nd clutch pressure and power is not transmitted to the 2nd clutch.
Line pressure (4) also flows to the servo valve and line pressure (l ) also flows to throttle valve B.
NOTE: When used, "|eft" or "right" indicates direction on the hydraulic circuit.
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Description
Hydraulic Flow (cont'dl
lll Position
The flow of fluid th.ough the torque converter circuit is the same as in S postion. The line pressure (1) tlows through themanual valve and becomes line pressure (3). lt then flows through the 1-2 shift valve to the servo valve via the servo con-trol valve, causing the shift fork shaft to be moved in the reverse direction.
Under this condition, the shift control solenoid valve A is turned ON whereas the valve B is turned OFF as in 3rd gear in
E ot O"- position. As a result. the 1-2 shift valve is also moved to the left. The fluid (3') will flow through tne servo varve
and manual valve to the 4th clutch; power is transmitted through the 4th clutch.
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E Position
The flow of tluid through the torque converter circuit is the same as in L\l]position. The line pressure (1) becomes line
pressure (3) as it passes through the manual valve. Then line pressure (3) flows through the 1-2 shift valve to the servo
valve via the servo control valve, causing the shift fork shaft to be moved to the reverse position as in @ position.
However, the hydraulic pressure is not supplied to the clutches. Power is not transmitted.
NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.
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Description
Lock-up System
Lock-up Clutch
1. Operation (clutch on)
With the lock-up clutch on, the fluid in the chamber between the torque converter cover and lock-up piston is discharged,
and the converter fluid exerts pressure through the piston against the converter cover, As a result, the converter turbine islocked on the converter cover firmly. The effoct is to bypass the converter, thereby placing the vehicle in direct drive.
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The power flows by way of:
Engine
I
Drive plate
I
Torque converter
I
Lock-up piston
I
Damper spring
I
Turbine
I
Mainshatt
2. Operation (clutch otl)
With the lock-up clutch oft, the tluid flows in the reverse of "clutch on." As a result, the lock-up piston is moved away
from the converter cover; that is, the torque converter lock-up is released.
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Engine
I
Drive plate
I
Torque converter cover
I
Pump
I
Turbine
Mainshaft
LOCK-UP PISTON
TOROUE CONVERTERCOVER
:1
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TURBINE
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In E position in 2nd, 3rd and 4th, and E position in 3rd, pressurized fluid is drained from rhe 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 crankshatt. Together with hydraulic control, the TCM op-
timized the timing of the lock-up system. Under certain conditions, the lock-up clutch is applied during deceleration in
3rd and 4th gear.
The lock-up system controls the range of lock-up according to lock-up control solenoid valves A and B, and the 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.
LOCK,UP CONTROL
LOCT.UP SHIfT VALVE
AlF COOIER
tocK uP coNTno! valvE
Solenoid valve
L*r""r "o.Jtio" \B
Lock'up OFFOFFOFF
Lock-up, slightONOFF
Lock-up, halfONON
Lock-up, fullONON
LOCK-Updu.ing decelerationONDuty operationOFF - ON
IOCK UP TIMING B VATVE
(cont'd)
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Description
LOC(,UP SlllFT VATVE
Lock-up System (cont'd)
No Lock-ug
The pressurized fluid regulated by the modulator works on both ends of the lock-up shift valve and on the left side ot
the lock-up control valve. Under this condition, the pressures working on both ends of the lock-up shift valve are equal.
the shift valve is moved to the right side by the tension of the valve spring alone. The tluid from the ATF pump will llow
through the left side of the lock-up clutch to the torque converter; that is, the lock-up clutch is in OFF condition.
NOTE: When used, "left" or "right" indicates direction on the hydraulic circuit.
LOCX.UP CONTROI
LOCK.UP COITTFOT VATVE
MOOUTATOR PRESSURE
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il
rl
I
IOCK IJP TIMING B VALVE
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IPartial Lock-up
Lock-uo Control Solenoid Valve A: ONLock-uD Control Solenoid Valve B: OFF
The TCM switches solenoid valve A ON to release modulator Dressure in the left cavity of the lock-up shift valve.
Modulator pressure in the right cavity of the lock-up shift valve overcomes the spring force, 8nd the lock-up shift valve is
moved to the left side,
Modulator pressure is separated into the two passages:
Torque Converter Inner Pressure: enters into right side to engage lock-up clutch,
Torque Converter Back Pressure: enters into left side to disengage lock-up clutch.
Back prassure {F2) is regulated by the lock-up control valve whereas the position of the lock-up timing B valve is deter-
mined by the throttle B pressure, tension of the valve spring, and pressure regulated by the modulator. Also the position
of the lock-up control valve is determined by the back prossure of the lock-up control valve and torque converter pressure
regulated by the check valve. With lock-up control solenoid valve B kept OFF. modulator pressure is maintained in the left
end of the lock-up control valve; in other words, the lock-up control valve is moved slightly to the left side. This slight
movement of the lock-up control valve causes the back pressure to be lowered slightly, resulting in partial lock-up.
NOTE: When used, "|eft" or "right" indicates direction on the hydraulic circuit.
LOCK.UP GO TNOLSOLENOIO VAIVE A
TOCK-UP SHIFT VAIVELOCI( UP COI{TROL VAIVE
T
LOC(,UP IM TG g VALV€
MODULATOB PNESSUFE
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'Full Lock-up
Lock-up Control Solenoid Valve A: ONLock-uD Contorl Solenoid Valve B:ON
When the vehicle speed further increases, throttle B pressure is increased in accordance with the throttle opening.
The lock-up timing B valve overcomes spring force and moves to the left side. Also, this valve closes the port leading to
the torque convener check valve.
Under this condition, throttle B pressure working on the right end of the lock-up control valve becomes greater than that
on the left end (modulator pressure in the left end has already been released by the solenoid valve B); the lock-up control
valve is moved to the left. As this happens, torque converter back pressure is fully released, causing the lock-up clutch to
be tully engaged.
NOTE: When used, "lelt" or "right" indicates direction on the hydraulic circuit.
LOC( UP CONiBOT
LOCK UP SHIFT VAIVE
MODULATOR PBESSURE
ATF COOLER
I
IOC( UP TIMING B VALVE
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