Expedition 4WD V8-4.6L SOHC VIN W (1999)
Positive Crankcase Ventilation Valve: Customer Interest
Engine - High Idle and Sticking Throttle When Cold
Article No.
01-21-12
10/29/01
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IDLE - HIGH IDLE SPEEDS - THROTTLE STICKS
AFTER STEADY STATE DRIVING IN EXTREME
COLD AMBIENT TEMPERATURES ---- VEHICLES
BUILT 12/2/1997 THROUGH 7/15/1999 EQUIPPED
WITH 5.4L ENGINE
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ENGINE - 5.4L - PCV SYSTEM ICING - VEHICLES
BUILT 12/2/1997 THROUGH 7/15/1999 ONLY
FORD:
1998-1999 EXPEDITION, F-150, F-250 LD
LINCOLN:
1999 NAVIGATOR
This article is being republished in its entirety to update the Service Procedure, Service Parts and the model years involved.
ISSUE
In rare instances, throttle sticking may occur on a few vehicles in very cold ambient temperatures after operating at steady speed or extended idle for a
period of time. This may be due to ice build-up from moisture in the Positive Crankcase Ventilation (PCV) gas on the throttle plate or throttle body.
ACTION
Verify the condition is not caused by throttle body sludging, throttle cable binding, or interference between an improperly positioned floor mat and
accelerator pedal. If no other conditions are identified, check for evidence of PCV system backflow. Refer to the following Service Procedure for details.
SERVICE PROCEDURE
Inspect the inside of the clean air tube at the PCV closure hose connection for presence of moisture, oil, or oily stains. If evidence of PCV system
backflow is found, replace the PCV system with the revised PCV service parts, PCV valve YC2Z-6K773-AA, and hose, YL3Z-8A505-BA.
To Install The Heated PCV Valve, Use The Following Procedure:
1.
Partially drain off enough coolant into a clean, suitable container to allow hose disassembly at the top of the engine, approximately 3.8L - 7.5L (1-2
gallons) and save coolant.
2.
Remove the PCV valve by disconnecting the vent hose and removing the valve from the valve cover grommet. Ensure the area is clean to prevent
dirt entry into engine.
3.
Install the new, heated PCV valve in the valve cover grommet.
