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 the Stall Speed Test or further transaxle damage will occur. Do not maintain wide open throttle in any transaxle range for more than 5 seconds.
This test verifies that the line pressure is within specification.
- Connect a pressure gauge to the line pressure tap.
- Start the engine and check the line pressures see the LINE PRESSURE CHART to determine if the line pressure is within specification.LINE PRESSURE CHART
Gear EPC Line Pressures at Idle (1) P 10-20 60-84 R 10-20 78-108 N 10-20 60-84 D 10-20 56-84 3 30-40 102-138 1 15-40 67-155 Pressure at Wide Open Throttle (WOT) Stall (1) P - - R 70-90 265-328 N - - D 70-90 208-257 3 70-90 208-257 1 70-90 208-257 (1) All pressures are in PSI and are approximate. - If the line pressure is not within specification, check EPC pressure.
- Connect a pressure gauge to the EPC pressure tap.
- Start the engine and check the EPC pressure. See the LINE PRESSURE CHART for specifications.
- If the EPC pressure is not within specification, GO to PINPOINT TEST E to diagnose the EPC operation. If EPC operation is OK, see the LINE PRESSURE DIAGNOSIS CHART for line pressure concern causes.
LINE PRESSURE DIAGNOSIS CHART
| Test Results | Possible Source |
|---|---|
| HIGH at IDLE - ALL RANGES | Wiring Harnesses EPC Solenoid Main Regulator Valve |
| LOW at IDLE - ALL RANGES | Low Fluid Level Fluid Inlet Filter/Seal Main Control Body Cross Leaks Gaskets Pump Separator Plate |
| LOW in Park ONLY | Valve Body |
| LOW in Reverse ONLY | Separator Plate Reverse Clutch Valve Body Forward Clutch |
| LOW in Neutral ONLY | Valve Body |
| LOW in Overdrive ONLY | Forward Clutch Valve Body |
| LOW in Drive ONLY | Forward Clutch |
| LOW in Manual 1st ONLY | Forward Clutch Valve Body |