Torque Converter Stall Test

CONVERTER STALL TEST
Stall test consist of determining maximum engine speed obtained at full throttle in "D" and "R" positions. This test checks torque converter stator overrunning clutch operation, and holding ability of transaxle clutches and low-reverse brake.

Warning:
During this test, make sure that no one stand in front of or behind vehicle.

1. Check transaxle fluid level. Fluid should be at normal operating temperature [70-80°C (158-176°F)]. Engine coolant should also be at normal operating temperature [80-90°C (176-205°F)].
2. Apply chocks to both rear wheels.
3. Attach an engine tachometer.
4. Apply the parking and service brakes fully.
5. Start the engine.
6. With the selector lever in the "D" position, depress the accelerator pedal fully to read maximum engine rpm. Do not hold the throttle wide open any longer than is necessary to obtain maximum engine rpm reading, and never longer than 5 seconds at a time. If more than one stall test is required, operate the engine at approximately 1,000 rpm in neutral for 2 minutes to cool the transaxle fluid between tests.

Stall speed: 1,800-2200 rpm

7. Place the selector lever in the "R" position and perform the stall test by the same procedure as previously described.

Stall Speed Above Specification in "D"
If stall speed is higher than specification, rear clutch or overrunning clutch of transaxle is slipping. In this case, perform hydraulic test to locate cause of slippage.

Stall Speed Above Specification in "R"
If the stall speed is higher than specification, the front clutch of the transaxle or low-reverse brake is slipping. In this case, perform the hydraulic test to locate the cause of slippage.

Stall Speed Below Specification In "D" and "R"
If the stall speed is lower than specification, insufficient engine output or a faulty torque converter is suspected. Check for engine misfiring, improper ignition timing, or valve clearance etc. If these are good, the torque converter is faulty.