2020 Subaru Forester BaseFACTORY OEM SERVICE PROCEDURE

Stall Test: Inspection

WARNING: During the stall test, confirm safety in the vicinity and make sure no person is around the vehicle.

Purposes of the stall test:

  • Operational check of forward clutch and reverse brake
  • Operational check of the torque converter
  • Engine performance check
  1. Check the engine oil level. Refer to LUBRICATION (H4DO)>ENGINE OIL>INSPECTION .
  2. Check the engine coolant level. Refer to COOLING (H4DO)>Engine Coolant>INSPECTION .
  3. Connect the Subaru Select Monitor.
  4. Turn the ignition switch to ON. (Engine OFF)
  5. Display [ATF Temp.] and [Engine Speed].
  6. Turn off all systems causing an electrical load, such as headlights, A/C, seat heater and rear defogger.
  7. Apply the parking brake.
  8. Start the engine.
  9. Turn OFF the pre-collision brake function. (Models with EyeSight)
  10. Check the CVTF level. Refer to CONTINUOUSLY VARIABLE TRANSMISSION (TR580)>CVTF>INSPECTION .
  11. Warm up until [ATF Temp.] reaches to 60 - 80°C (140 - 176°F).
  12. Place wheel chocks at the front and rear of all wheels.
  13. Shift the select lever to "D range".
  14. Depress the accelerator pedal to the full while fully depressing the foot brake pedal with your left foot.
    CAUTION:
    • Do not perform the stall test for five seconds or more at a time.

      Failure to follow this instruction may accelerate the engine oil and CVTF deterioration and affect the engine and transmission adversely.

    • If the stall speed is higher than the specified range, attempt to finish the stall test in as short a time as possible, in order to prevent the transmission from sustaining damage.
  15. When the engine speed stabilizes, quickly record [Engine Speed] and release accelerator pedal.

    Standard: 

    1, 950 - 2, 550 r/mn

    Stall test judgment 

    Stall speed (at sea level) Range Probable cause
    Lower than standard value D
    • Insufficient engine output
    • Torque converter malfunction
    Higher than standard value
    • Forward clutch slippage
    • Secondary pressure (line pressure) is low.
    • Variator chain malfunction
    • Torque converter malfunction
    • Control valve body malfunction
    • TCM malfunction
    • Damaged harness and harness connector
  16. Shift the select lever to "N range", and idle the engine for one minute or more.
  17. Shift the select lever to "R range" and perform the stall test in the same manner.

    Standard: 

    1, 850 - 2, 450 r/mn

    Stall test judgment 

    Stall speed (at sea level) Range Probable cause
    Lower than standard value R
    • Insufficient engine output
    • Torque converter malfunction
    Higher than standard value
    • Reverse brake slippage
    • Secondary pressure (line pressure) is low.
    • Variator chain malfunction
    • Torque converter malfunction
    • Control valve body malfunction
    • TCM malfunction
    • Damaged harness and harness connector
Factory Service Tools

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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.

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