Line Pressure Test

CAUTION: Carry out the line pressure test prior to carrying out the stall speed test. If the line pressure is low at stall, do not carry out stall speed test or further transmission damage will occur. Do not maintain WOT in any transmission range for more than five seconds.

This test verifies that the line pressure is within specification.

Connect pressure gauge to line pressure tap.
Start engine and check line pressures. Refer to the Line Pressure Chart to determine if line pressure is within specification.

Fig 1: Identifying Line Pressure Chart
Courtesy of FORD MOTOR CO.

Fig 2: Identifying Clutch Pressure Chart

Courtesy of FORD MOTOR CO.

EPC readings will vary due to EEC strategy. These values are approximate pressures. Actual clutch pressures should be within 69-103 kPa (10-15 psi) of line pressure. For additional information on testing, refer to CLUTCH PRESSURE TEST .
Place the ignition switch in the OFF position. If line pressure is not within specification, check EPC pressure.
Connect pressure gauge to EPC pressure tap.
Start engine and check EPC pressure. Use the line pressure chart for specifications.
If EPC pressure is not within specification, carry out PINPOINT TEST E to diagnose EPC operation. If EPC operation is OK, see the line pressure diagnosis chart for line pressure concern causes.

Fig 3: Identifying Line Pressure Diagnosis Chart (1 Of 2)
Courtesy of FORD MOTOR CO.

Fig 4: Identifying Line Pressure Diagnosis Chart (2 Of 2)

Courtesy of FORD MOTOR CO.