Checking Line Pressure and Stall Speed

Checking Line Pressure And Stall Speed
Special tools: 999 253, 999 5074





- Check fluid level.
- Attach pressure gauge 999 2531 to side window.
- Remove front plug on transmission and install connector 999 5074.
- Attach tube to connector.

NOTE: Since line pressure is the pressure in clutch CO, there is no pressure in 4th gear when CO is idle.

- Start engine and allow to idle with gear selector in position N.
- Check idling speed.

Line Pressures:

- Depress brake pedal and move gear selector to different positions and read line pressure in each, compare readings to chart.





Measure Stall Speed When Measuring Line Pressure
Check provides information mainly on condition of torque converter, transmission clutches and engine.

- In order for test to give correct results:
A - engine must deliver full power.
B - line pressure must be correct.
C - transmission fluid level and operating temperature must be correct.

NOTE: Never carry out stall speed check if line pressure is too low.

- Air conditioning (A/C) system must be switched off.
- Start engine. Apply handbrake and press brake pedal hard with left foot.





- Move gear selector to position D, press accelerator to floor for a maximum of 5 seconds and read maximum speed shown on tachometer. Read line pressure and compare with values in table.

CAUTION: Never carry out stall speed check for more than 5 seconds.

- Repeat procedure with gear selector lever in position R.. Compare readings with values in table.
- If reading exceeds specified value, proceed to High Stall Speed. If reading is less than tabulated value, Low Stall Speed.

High Stall Speed
Assuming that conditions specified in Line Pressure Check are fulfilled and time of acceleration from 0 to 100 km/h (0-60 mph) is normal and measured stall speed exceeds normal value by more than 300 RPM:
- Check if fluid is discolored or gives off burnt odor. If so, check DTC 2-3-5, and change fluid.
- If fluid is OK, replace torque converter.
- Fluid contamination indicates worn or burnt clutch plates. In this case, replace transmission.

Low Stall Speed
Requirements: Same test conditions as specified in High Stall Speed and measured stall speed is more than 300 RPM below normal value:
- Try with new torque converter.Recheck stall speed after replacing torque converter.
- If fault is still present, replace the transmission.

Noise
- Replace transmission.
- Recheck stall speed after replacing transmission.