Line Pressure/EPC Pressure Test

CAUTION: Perform the line pressure test prior to performing the stall speed test. If the line pressure is low at stall, do not perform stall speed test or further transmission damage will occur. Do not maintain Wide Open Throttle (WOT) in any transmission range for more than five seconds.

This test verifies that the line pressure is within specification.








1. Connect pressure gauge to line pressure tap.





2. Start engine and check line pressures.
3. If line pressure is not within specification, check Electronic Pressure Control (EPC) pressure.
4. Connect pressure gauge to EPC pressure tap.
5. Restart engine and check EPC pressure.

Line Pressure Test Chart:

6. If EPC pressure is not within specification, perform Pinpoint Test E to diagnose EPC operation. If EPC operation is OK, refer to Line Pressure Diagnosis Chart for line pressure concern causes.