Air Pressure Check

WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2006 Ford RV Cutaway, 2006 Ford Pickup, 2006 Ford F550 Super Duty, 2006 Ford F450 Super Duty, and 2006 Ford Econoline. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: An air leak on the high pressure oil pump shaft lip seal is normal while carrying out this procedure. This is not an indication of a high pressure oil leak and the high pressure oil pump should not be replaced for this condition.

NOTE: The replacement parts may leak if all the surfaces are not oil saturated under system pressure and the seals are not properly seated during installation.

Verify base engine oil pressure. Refer to ENGINE - 6.0L DIESEL .
Key ON, engine OFF. Using the diagnostic tool, close the IPR valve by increasing the IPR duty cycle.
Slowly apply regulated shop-air pressure to the high pressure oil rail through the ICP port, using the Adapter, High Pressure Pump Test 303-765 or equivalent.
Using the diagnostic tool open the IPR valve by decreasing the IPR duty cycle. Allow oil to drain through the IPR valve. An air leak should be heard. Using the diagnostic tool, close the IPR valve by increasing the IPR duty cycle. If no change is heard, the IPR valve may not be functioning as commanded. GO to Pinpoint Test R for IPR circuit DTCs. If no DTCs are present, install a new IPR valve and repeat the test.
Using the diagnostic tool, increase the IPR duty cycle to close the IPR valve. If the no start condition exists, an audible leak may be identified by using a stethoscope through the oil fill tube or left valve cover crankcase vent hole. If a small leak condition, an intermittent no start condition, or the ICP elevated pressure after a 15 minute soak and engine start condition exists, remove the valve covers to inspect for leaks. Refer to ENGINE - 6.0L DIESEL .
Slowly apply regulated shop air pressure to the right high pressure oil rail through the ICP port, using the Adapter, High Pressure Pump Test 303-765 or equivalent, or fill port using the Adapter, High Pressure Rail Test 303-766 or equivalent. Check for leaks. A stethoscope may be used to help identify the leak.
Repair any leaks as necessary and repeat the air pressure check for leaks. Continue diagnosis if the concern still exists.
Disconnect shop air pressure supply. Install an ICP sensor or plug.
Slowly apply regulated shop air pressure to the left high pressure oil rail through the ICP port, using the Adapter, High Pressure Pump Test 303-765 or equivalent, or fill port using the Adapter, High Pressure Rail Test 303-766 or equivalent.
Using the diagnostic tool open the IPR valve by decreasing the IPR duty cycle. Allow oil to drain through the IPR valve. An air leak should be heard. Using the diagnostic tool, close the IPR valve by increasing the IPR duty cycle.
IPR valve closed. Check the left high pressure oil rail for leaks. A stethoscope may be used to help identify the leak.
Repair any leaks as necessary and test for leaks. Continue the diagnosis if the concern still exists.