Stall Test: Inspection

NOTE: The stall test is of extreme importance in diagnosing the condition of the automatic transmission and the engine. It should be conducted to measure the engine stall speeds in "R" and 2nd of manual mode. Purposes of the stall test:

To check the operation of the automatic transmission clutch.
To check the operation of the torque converter clutch.
To check engine performance.

Check that the throttle valve opens fully.
Check that the engine oil level is correct.
Check that the coolant level is correct.
Check that the ATF level is correct.
Check that the differential gear oil level is correct.
Increase ATF temperature to 70 - 80°C (158 - 176°F) by idling the engine for approximately 30 minutes (with select lever set to "N" or "P").
Place the wheel chocks at the front and rear of all wheels and apply the parking brake.
Move the manual linkage to ensure it operates properly, and then set to the 2nd on manual mode.

Fig 1: Identifying Manual Linkage In 2nd Gear
Courtesy of SUBARU OF AMERICA, INC.
While forcibly depressing the foot brake pedal, gradually depress the accelerator pedal until the engine operates at full throttle.

Fig 2: Identifying Accelerator/Brake Pedal Travel
Courtesy of SUBARU OF AMERICA, INC.
When the engine speed is stabilized, record that speed quickly and release the accelerator pedal.
Shift the select lever to "N" range, and cool down the engine by idling it for more than one minute.
If the stall speed in the 2nd of manual mode is higher than specifications, low clutch slipping and 2-4 brake slipping may occur. To identify it, conduct the same test as above in "R" range.
Perform the stall tests with the select lever in "D" range.
NOTE:
- Do not continue the stall test for more than five seconds at a time (from closed throttle, fully open throttle to stall speed reading). Failure to follow this instruction causes the engine oil and ATF to deteriorate and the clutch and brake to be adversely affected.
- Be sure to cool down the engine for at least one minute after each stall test with the select lever set in "P" or "N" range and with the idle speed lower than 1,200 RPM.
- 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 automatic transmission from sustaining damage.
Stall speed (at sea level):

2,300 - 2,700 RPM

STALL TEST

Stall speed (at sea level)	Range	Cause
Less than standard	2nd on manual mode, R	Throttle valve not fully open Erroneous engine operation Torque converter clutch's one-way clutch slipping
More than standard	D	Line pressure is too low Low clutch slipping One-way clutch malfunctioning
	R	Line pressure is too low Reverse clutch slipping Low & reverse brake slipping
	2nd on manual mode	Line pressure is too low Low clutch slipping 2-4 brake slipping