Torque converter stall test (STALL TEST)

The purpose of this test is to measure the maximum engine crankshaft speed with the automatic transmission output shaft fully locked in the "D" and "R" ranges. The test results can be used to determine the operation of the stator one-way clutch, as well as slippage in the friction clutches, the first gear brake and the reverse gear brake.

During this test, do not allow anyone to stand in front of or behind the vehicle.

1. Check the transaxle fluid (ATF) level and temperature, and the engine coolant temperature. The ATF level must be at the "HOT" mark on the dipstick. The ATF must be warmed up to normal operating temperature (70 - 80°C). The engine coolant must also be warmed up to normal operating temperature (80 - 90°C).

2. Place wheel chocks under the rear wheels of the vehicle.

3. Install a diagnostic tachometer to measure engine crankshaft speed.

4. Fully raise the parking brake lever and depress the brake pedal all the way.

5. Start the engine.

6. Move the A/T selector lever to the "D" position, then fully depress the accelerator pedal to determine the maximum engine speed at this point. During this test, do not hold the throttle valve fully open for longer than necessary to determine the maximum engine speed, or longer than 5 seconds.

If this test must be performed more than once, move the A/T selector lever to the "N" position after each test and run the engine at 1000 rpm for 2 minutes to cool the A/T fluid (ATF) between tests.

Standard value:

Engine speed with vehicle fully stalled (STALL TEST): 2300 - 2700 rpm. 7. Move the selector lever to the "R" position and repeat the stall test with the vehicle fully stalled, as described in the steps above.

WHEN TESTING IN "D" RANGE WITH THE VEHICLE FULLY STALLED, ENGINE SPEED IS ABOVE THE SPECIFIED VALUE

If engine speed is above the specified value, the rear clutch or the transmission overrunning clutch is slipping. In this case, perform the A/T hydraulic control system pressure test to determine the cause of the slipping.

WHEN TESTING IN "R" RANGE WITH THE VEHICLE FULLY STALLED, ENGINE SPEED IS ABOVE THE SPECIFIED VALUE

If engine speed is above the specified value, the front clutch, the 1st gear brake, or the reverse gear brake is slipping. In this case, perform the A/T hydraulic control system pressure test to determine the cause of the slipping.

WHEN TESTING IN "N" RANGE WITH THE VEHICLE FULLY STALLED, ENGINE SPEED IS BELOW THE SPECIFIED VALUE

If engine speed is below the specified value, the cause is insufficient engine output or a malfunction of the torque converter. Check for misfires, ignition timing, valve train clearance, etc. If no faults are found in all of the above items, the torque converter is faulty.