Line Pressure Test: Procedure

Fig 1: Illustrating Line Pressure Test Procedure

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Start engine.
Check idle speed in P range, refer to Emission control.
Idle speed: 750-850 rpm (with parking brake applied)
Shift selector lever to D range and read line pressure at idle.
CAUTION: Perform steps 4 and 5 within five seconds to prevent possible transaxle damage.
Depress brake pedal firmly with left foot and gradually depress accelerator pedal fully with the right foot.
Read line pressure as soon as engine speed becomes constant and release accelerator pedal.
NOTE: Idling for at least one minute cools ATF and prevents deterioration.
Shift selector lever to N range and run engine at idle for at least one minute.
Read line pressure at idle and at engine stall speed for each range in same manner.
Specified line pressure shown in Fig 2 : psi (kPa, kg/cm² )

Fig 2: Line Pressure Range Chart
Courtesy of KIA MOTORS AMERICA, INC.
Install a new square-head "L" plug in inspection port, refer to Line pressure test .
Tightening torque: 44-86 lb.in (5.0-9.8 N.m, 51-100 kg.cm)

Evaluation of line pressure test

Fig 3: Line Pressure Possible Cause Chart
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