System Pressure And Stall Speed, Check
Line pressure/stall speed, checking
Special tools:
999 2531 MANOMETER 999 2531 Manometer
999 5728 Nipple 999 5728 Nipple
Preparations
Ignition off.
Remove the air cleaner (ACL) housing
See: Brake pipe master cylinder / ABS unit, replacing Brake Pipe Master Cylinder / ABS Unit, Replacing.
Remove the transmission cable from the bracket
Ensure that the cable and sleeve do not crack or break.
Move the cable to one side. Remove the front screw. Slacken off the rear screw for the cable bracket slightly.
Blow the test output plug clean with compressed air. Remove it. Install the connector nipple
Install nipple 999 5728 Nipple 999 5728 Nipple.
Note! Conical screw threads. Do not over tighten.
Connect the hose and manometer 999 2531 MANOMETER 999 2531 Manometer to the nipple. Position the manometer so that it is clearly visible from the driver's seat.
Press the transmission cable into place on the bracket
Turn the cable bracket out towards the fender liner.
Press the transmission cable into place on the bracket.
Tighten the bracket rear screw slightly.
Connect the air cleaner (ACL) housing temporarily
Make sure that the intake manifold is connected with the clamp. Otherwise air leakage may be registered and diagnostic trouble codes (DTCs) stored.
Note! Ensure that the transmission is at normal operating temperature before stalling. Stalling is an inappropriate method for warming up the transmission. The method can cause local and uneven overheating. It is better to run the transmission to operating temperature.
Check the system pressure and the stalling speed
Note! Always wait after the gear selector has been moved, so that the pressure stabilizes before reading off.
Check the stall speed when checking the line pressure
The stall speed test gives an indication of the condition of the torque converter, the transmission clutches and the engine.
In order for the test to give accurate results:
- the engine must be properly tuned
- the line pressure must be correct
- the oil level in the transmission must be correct and the transmission must be at operating temperature.
Note! Never conduct a stall speed check when the line pressure is too low.
Check
Connect a tachometer so that it can be read from the driver's seat.
The air conditioning (A/C) system must be switched off.
Block all four wheels.
Start the engine.
Note! Apply the parking brake. Press down hard on the brake pedal with your left foot during the test.
Move the gear shift to position D. Fully depress the accelerator pedal (AP) for a maximum of 5 seconds. Read off the highest engine speed (RPM) and the line pressure. Compare to the table below.
Note! Do not test the stall speed for more than 5 seconds.
Normal stall speed at sea level and +20°C air temperature (engine speed (RPM) reduces by 120 rpm per 1000 meters above sea level and by 50-100 rpm per 10°C above +20°C air temperature).
Repeat the tests with the gear selector in position R. Compare to the table.
If the engine speed (RPM) exceeds the value in the table, see High stall speed below.
If the engine speed (RPM) is below the value in the table, see Low stall speed below.
High stall speed
The test conditions described in Check the stall speed when checking the line pressure above have been met.
Is acceleration from 0-100 km/h normal?
If the stall speed recorded exceeds the normal value by more than 300 rpm:
Replace the transmission
Low stall speed
The test conditions described in Check the stall speed when checking the line pressure above have been met.
If the stall speed recorded is below the normal value by more than 300 rpm:
Replace the transmission
Ignition off. Remove the air cleaner (ACL) from the hose and disconnect connector
Disconnect the cable from the bracket and rear bracket screw.
Remove hose, manometer and nipple.
Finishing work
Install plug with new test output.
Tighten the cable bracket to the transmission. Tighten to 25 Nm. Press cable into place on the bracket.
Install the air cleaner (ACL) housing
See: Brake pipe master cylinder / ABS unit, replacing Brake Pipe Master Cylinder / ABS Unit, Replacing.