Special Testing Procedures

SPECIAL TESTING PROCEDURES
The special tests are designed to aid the technician in diagnosing the hydraulic and mechanical portion of the transaxle.

Engine Idle Speed Check
See ELECTRONIC ENGINE CONTROL (EEC) SYSTEM for the engine idle speed adjustment procedure.

Line Pressure Test

Caution
^ Carry out the Line Pressure Test before carrying out the Stall Speed Test. If line pressure is low at stall, do not carry out stall test or further transaxle damage may occur. Do not maintain Wide Open Throttle (WOT) in any gear range for more than 5 seconds.

Caution
^ The transaxle tester must be removed from the transaxle and the vehicle harness connected to verify these pressures.

The Line Pressure Test verifies that the line pressure is within specifications.
1. Remove the line pressure port plug.
2. Connect pressure gauge to the line pressure tap.
3. Start engine and check line pressures. Refer to the following Line Pressure Chart to determine if line pressure is within specifications.

Line Pressure Tap

Line Pressure Chart (2.3L And 3.0L):

4. If line pressure is not within specifications, carry out on-board diagnostics and pinpoint test, air pressure check and repair main control system or pump as required.
5. After completing the line pressure test, install the line pressure port plug.
^ Tighten to 14 N-m (1.0 kgf-m, 10 ft-lbf).

Line Pressure Chart (2.3L and 3.0L)

Line Pressure Tap:

Line Pressure Diagnosis
If the line pressure is low at idle in all ranges check the following items:
^ Low fluid level
^ Restricted inlet filter
^ Loose main body
^ Solenoid body or accumulator body to case bolts
^ Excessive leakage in pump
^ Case
^ Control bodies
^ Sticking main regulator valve or damaged inlet tube seal on inlet filter
^ Damaged gaskets or separator plate
If the line pressure is high at idle in all ranges then check the following items:
^ Main regular valve
^ Solenoid body and wiring harness
^ Run Quick Test referred to in electrical diagnosis

Stall Speed Test
The Stall Speed Test checks the operation of the following items:
^ Torque converter one-way clutch
^ Forward clutch
^ Low/reverse one-way clutch
^ Reverse clutch
^ Forward one-way clutch
^ Engine driveability concerns
1. Connect a tachometer to the engine.

Warning
^ Apply the service and parking brakes firmly while carrying out each stall test. Failure to set the brakes can result in death or bodily injury.

Caution
^ Carry out Line Pressure Test before carrying out the stall test. If line pressure is low at stall, do not carry out stall test or further transaxle damage may occur.

Note
^ The stall test should only be carried out with the engine and transaxle at normal operating temperatures.

2. Press accelerator pedal to floor (WOT) in each range. Record rpm reached in each range. Stall speeds should be in appropriate range.

Caution
^ Do not maintain wide open throttle (WOT) in any gear range for more than 5 seconds.

Caution
^ If engine rpm recorded by the tachometer exceeds maximum specified rpm, release accelerator pedal immediately. Clutch or band slippage is indicated.

Stall Speed Chart

Stall Speed Chart:

After testing DRIVE (D) and REVERSE (R), move transaxle range selector lever to NEUTRAL (N) and run engine for about 15 seconds to allow torque converter to cool before testing next range.
If the stall speeds were too high, see the following Stall Speed Diagnosis Chart. If the stall speeds were too low, first check engine tune-up. If engine is OK, remove torque converter and check torque converter one-way clutch for slippage.

Stall Speed Diagnosis Chart

Stall Speed Diagnosis Chart:

Air Pressure Tests
A no-drive condition can exist even with correct transaxle fluid pressure because of inoperative clutches or bands. Refer to the Band and Clutch Application Charts A and B to determine the appropriate elements. A clutch concern can be located by substituting air pressure for oil pressure to determine the location of the malfunction.
For example, when the transaxle range selector lever is in a forward gear range ((D), 2, 1), a no-drive condition can be caused by an inoperative forward clutch.

Test Procedures
Carry out the following procedures:
1. Drain the transaxle. Remove the main control cover.
2. Remove the main control as an assembly with the solenoid body assembly.
3. The inoperative clutches can be located by applying air pressure into the appropriate clutch port. See the Air Pressure Test Port Locations diagram.
4. Install the transaxle test plate using six bolts.
^ Tighten to 12 N-m {1.2 kgf-m, 9 ft-lbf}.

5. Caution
^ The coast clutch circuit should not be applied unless air pressure is maintained in the forward clutch circuit. Failure to do so can result in the coast clutch piston coming out of the forward clutch piston.

Note
^ See the Band and Clutch Application Charts A and B.

Apply air pressure 275 kPa (40 psi) to the appropriate clutch port (refer to Air Pressure Test Port Locations diagram). A dull thud may be heard, or movement felt when the clutch piston is applied. If clutch seals or check balls are leaking, a hissing may be heard.

Air Pressure Test Results
If the servos do not operate, disassemble, clean and inspect them to locate the source of the concern.
If air pressure applied to the clutch passages fails to operate a clutch, or operates clutches simultaneously, inspect the fluid passages in the case.
If air pressure applied to the accumulator fails to operate an accumulator, remove and inspect the case passages and piston.

Air Pressure Test Port Locations

Air Pressure Test Port Locations: