Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Mechanical System Tests
- STALL SPEED TEST
HINT:
This test is to check the overall performance of the engine and transmission.
NOTE:- Do not perform the stall speed test longer than 5 seconds.
- To ensure safety, perform this test in an open and level area that provides good traction.
- The stall speed test should always be performed with at least 2 people. One person should observe the condition of the wheels and wheel chocks while the other is performing the test.
- Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
- Run the vehicle until the transmission fluid temperature has reached 50 to 80°C (122 to 176°F).
- Allow the engine to idle with the air conditioning OFF.
- Chock all 4 wheels.
- Set the parking brake and keep the brake pedal depressed firmly with your left foot.
- Move the shift lever to the D position.
- Depress the accelerator pedal as much as possible with your right foot.
- Read the engine rpm (stall speed) and release the accelerator pedal immediately.
Standard value: 2,350 to 2,550 rpm
Evaluation:
RESULT REFERENCE CHARTTest Result Possible Cause Stall speed is lower than standard value - Stator one-way clutch is not operating properly
- Torque converter is faulty (stall speed is less than standard value by 600 rpm or more)
- Engine power may be insufficient
Stall speed is higher than standard value - Line pressure is low
- Forward clutch slipping
- No. 2 one-way clutch is not operating properly
- O/D one-way clutch is not operating properly
NOTE: Perform the test at the normal operating ATF temperature of 50 to 80°C (122 to 176°F).
- SHIFT TIME LAG TEST
HINT:
This test is to check the condition of the direct clutch, forward clutch, 1st brake and reverse brake.
- Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
- Run the vehicle until the transmission fluid temperature has reached 50 to 80°C (122 to 176°F).
- Allow the engine to idle with the air conditioning OFF.
- Set the parking brake and keep the brake pedal depressed firmly.
- Check the D range time lag.
- Move the shift lever to N and wait for 1 minute.
- Move the shift lever to D and measure the time until the shock is felt.
- Repeat the 2 procedures above 3 times, and calculate the average time of the 3 tests.
- Check the R range time lag.
- Move the shift lever to N and wait for 1 minute.
- Move the shift lever to R and measure the time until the shock is felt.
- Repeat the 2 procedures above 3 times, and calculate the average time of the 3 tests.
Standard value: D range time lag is less than 1.2 seconds
R range time lag is less than 1.5 seconds
Evaluation:
RESULT REFERENCE CHARTTest Result Possible Cause D range time lag exceeds standard value - Line pressure is low
- Forward clutch is worn
- O/D one-way clutch is not operating properly
R range time lag exceeds standard value - Line pressure is low
- Direct clutch is worn
- 1st and reverse brake is worn
- O/D one-way clutch is not operating properly
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.