Stall Test - Subaru Legacy 2002 Service Manual

5. Stall Test

S502246
A: INSPECTION
1. GENERAL INFORMATION
The stall test is of extreme importance in diagnos-
ing the condition of the automatic transmission and
the engine. It should be conducted to measure the
engine stall speeds in R and 2 ranges.
Purposes of the stall test:
1) To check the operation of the automatic trans-
mission clutch.
2) To check the operation of the torque converter
clutch.
3) To check engine performance.
2. TEST METHODS
1) Preparations before test:
(1) Check that throttle valve opens fully.
(2) Check that engine oil level is correct.
(3) Check that coolant level is correct.
(4) Check that ATF level is correct.
(5) Check that differential gear oil level is cor-
rect.
(6) Increase ATF temperature to 50 to 80°C
(122 to 176°F) by idling the engine for approxi-
mately 30 minutes (with select lever set to "N"
or "P").
2) Install an engine tachometer at a location vis-
ible from the driver's compartment and mark the
stall speed range on the tachometer scale.
3) Place the wheel chocks at the front and rear of
all wheels and engage the parking brake.
4) Move the manual linkage to ensure it operates
properly, and shift the select lever to the 2 range.
5) While forcibly depressing the foot brake pedal,
gradually depress the accelerator pedal until the
engine operates at full throttle.
(A) Brake pedal
(B) Accelerator pedal
6) When the engine speed is stabilized, read that
speed quickly and release the accelerator pedal.
7) Shift the select lever to Neutral, and cool down
the engine by idling it for more than one minute.
8) Record the stall speed.
STALL TEST
S502246A10
S502246A1001
S502246A1002
B3M1589B
9) If stall speed in 2 range is higher than
specifications, low clutch slipping and 2-4 brake
slipping may occur. To identify it, conduct the same
test as above in D range.
10) Perform the stall tests with the select lever in
the R range.
NOTE:
¼ 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 the P or N range and with the idle speed lower
than 1,200 rpm.
¼ 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):
2.0 L model: 2,000 — 2,500 rpm
Except 2.0 L model: 2,100 — 2,600 rpm
AT-13
Automatic Transmission