Line Pressure Test

WARNING: This page is about a different car, the 2003 Ford Pickup, 2003 Ford F550 Super Duty, 2003 Ford F450 Super Duty, 2003 Ford Excursion, and 2003 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Locating Line Pressure Test Tap

Courtesy of FORD MOTOR CO.

CAUTION: Carry out the Line Pressure Test prior to carrying out the Stall Speed Test. See STALL SPEED TEST . If line pressure is low at stall, do not carry out the Stall Speed Test or further transmission damage will occur. Do not maintain wide-open throttle in any transmission range for more than 5 seconds or transmission damage may occur.

NOTE: If the Transmission Tester is installed it must be removed prior to carrying out the test.

NOTE: If equipped, turn the Power Take-Off (PTO) unit off for correct test results. For a description of PTO operation, refer to Transmission Electronic Control System.

NOTE: Carry out shift linkage check prior to carrying out this test; refer to ADJUSTMENTS .

This test verifies the line pressure is within specifications.

Connect the Pressure Gauge to the line pressure tap.
Start the engine and check the line pressures. Refer to the Line Pressure Chart to determine if the line pressure is within specification.
If the line pressure is not within specifications, carry out On-Board Diagnostics and GO to PINPOINT TEST E: DIGITAL TRANSMISSION RANGE (EPC) SOLENOID , AIR PRESSURE CHECKS , and clean, inspect and install a new main control system or pump as required.

Fig 2: Line Pressure Chart (Power Take-Off Must Be Turned Off Prior To Carry Out Test)
Courtesy of FORD MOTOR CO.

Fig 3: Line Pressure Diagnosis Chart
Courtesy of FORD MOTOR CO.