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Mechanical System Tests

  1. STALL SPEED TEST 

    HINT:

    This test is to check the overall performance of the engine and transmission.

    CAUTION:
    • Driving test should be done on a paved road (a nonskid road).
    • 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.
    NOTE: Do not perform the stall speed test for longer than 5 seconds.
    1. Connect the Techstream to the DLC3.
    2. Run the vehicle until the transmission fluid temperature has reached 50 to 80°C (122 to 176°F).
    3. Allow the engine to idle with the air conditioning and headlights OFF.
    4. Chock all 4 wheels.
    5. Set the parking brake and keep the brake pedal depressed firmly with your left foot.
    6. Move the shift lever to the D position.
    7. Depress the accelerator pedal as much as possible with your right foot.
    8. Read the engine rpm (stall speed) and release the accelerator pedal immediately.

      Standard value: 

      2225+/-150 rpm 

      Evaluation: 

      TEST RESULT POSSIBLE CAUSE

      Test Result Possible Cause
      Stall speed is lower than standard value
      • Engine power output may be insufficient
      • Stator one-way clutch not operating properly

      HINT:
      If the value is less than the specified value by 600 rpm or more, the torque converter could be faulty.
      Stall speed is higher than standard value
      • Line pressure is too low
      • Forward multiple clutch (C1) slipping
      • No. 1 one-way clutch (F1) is not operating properly
      • Improper fluid level
      NOTE: Perform the test at the normal operating ATF temperature of 50 to 80°C (122 to 176°F).
  2. SHIFT TIME LAG TEST 

    HINT:

    When the shift lever is shifted while the engine is idling, there will be a certain time lapse or lag before the shock can be felt. This is used for checking the condition of the clutch, and brake.

    1. Connect the Techstream to the DLC3.
    2. Run the vehicle until the transmission fluid temperature has reached 50 to 80°C (122 to 176°F).
    3. Allow the engine to idle with the air conditioning OFF.
    4. Set the parking brake and keep the brake pedal depressed firmly.
    5. Check the D position time lag.
      1. Move the shift lever to N and wait for 1 minute.
      2. Move the shift lever to D and measure the time until the shock is felt.
      3. Repeat the 2 procedures above 3 times, and calculate the average time of the 3 tests.
    6. Check the R position time lag.
      1. Move the shift lever to N and wait for 1 minute.
      2. Move the shift lever to R and measure the time until the shock is felt.
      3. Repeat the 2 procedures above 3 times, and calculate the average time of the 3 tests.

        Standard value: 

        D position time lag is less than 0.8 seconds 

        R position time lag is less than 1.2 seconds 

        Evaluation: 

        TEST RESULT POSSIBLE CAUSE

        Test Result Possible Cause
        D position time lag exceeds standard value
        • Line pressure is low
        • Forward multiple clutch (C1) is worn
        • No. 1 one-way clutch (F1) is not operating properly
        R position time lag exceeds standard value
        • Line pressure is low
        • Reverse clutch (C4) is worn
        • No. 2 brake (B2) is worn
        • No. 1 one-way clutch (F1) is not operating properly
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