System Pressure And Stall Speed, Check

System pressure / stalling speed, checking

Special tools:
999 2531 MANOMETER 999 2531 Manometer
999 5074 NIPPLE 999 5074 NIPPLE

Checking the oil level
See Checking oil level Checking Oil Level.

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 and from the lever on the transmission
See.

Connecting the manometer




Remove the test plug from the transmission. Install nipple 999 5074 NIPPLE 999 5074 NIPPLE.
Connect the hose and manometer 999 2531 MANOMETER 999 2531 Manometer to the nipple.

Install the transmission cable on the transmission
See.

Install the air cleaner (ACL) housing
See Brake pipe master cylinder / ABS unit, replacing Brake Pipe Master Cylinder / ABS Unit, Replacing.

Checking the engine idling speed
Start the engine. Allow it to idle in neutral.
Check the engine idle speed. See the table below.

Checking the line pressure
Depress the brake pedal.
Move the gear selector into its various positions. Read off the line pressures.






Checking the stall speed
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.

For the test to be accurate the following conditions must be met:
- 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
The air conditioning (A/C) must be turned off. Block all four wheels. Start the engine.

Caution! Apply the parking brake. Press down hard on the brake pedal using your left foot during the test.

Move the gear selector to position D . Fully depress the accelerator pedal (AP) for a maximum of 5 seconds . Read off the maximum engine speed (RPM) and the line pressure. Compare to the table below.

Note! Do not test the stall speed for longer than 5 seconds.





Repeat the test with the gear selector in position R.
Compare to the table.
If the engine speed (rpm) exceeds the value in the table, see High stalling speed . If the engine speed (rpm) is less than the value in the table, see Low stalling speed .

High stalling speed
The test conditions described in Check 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:
Check if the oil is discolored or smells burnt. See Oil, quality check .
If the oil is OK, replace the torque converter: (See the procedures that also apply when replacing the torque converter).

- For gasoline engines: see and Transmission, installing Transmission, Installation
- Diesel engines: see and Transmission, installing Transmission, Installation.

Dirty oil indicates worn or burnt clutch plates. Replace the transmission:

- For gasoline engines: see and Transmission, installing Transmission, Installation
- Diesel engines: see and Transmission, installing Transmission, Installation.
Check the stalling speed again after replacing the transmission.

Low stalling speed




The test conditions described in Check above have been met.

Try a new torque converter if the stall speed recorded is below the normal value by more than 300 rpm:
For gasoline engines: see and Transmission, installing Transmission, Installation. Diesel engines: see and Transmission, installing Transmission, Installation.

Check the stalling speed again after replacing the torque converter. Replace the transmission if the fault persists:

- For gasoline engines: see and Transmission, installing Transmission, Installation
- Diesel engines: see and Transmission, installing Transmission, Installation.

Noise:

Replace the transmission:
- For gasoline engines: see and Transmission, installing Transmission, Installation
- Diesel engines: see and Transmission, installing Transmission, Installation.
Check the stalling speed again after replacing the transmission.

After the check is completed:
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.
Remove both the manometer connection and the manometer.

Install:
- the test plug. Check that the O-ring is undamaged. Replace if necessary. Tighten to 8 Nm
- the transmission cable
- the air cleaner (ACL) housing. See Brake pipe master cylinder / ABS unit, replacing Brake Pipe Master Cylinder / ABS Unit, Replacing.