Ford Aerostar 1986-1997 Repair Guide

PCV Valve



All models use a closed crankcase ventilation system with a sealed breather cap connected to the air cleaner by a rubber hose. The PCV valve is usually mounted in the valve cover and connected to the intake manifold by a rubber hose. The system is used to regulate the amount of crankcase (blow-by) gases which are recycled into the combustion chambers for burning with the normal fuel charge.

The only maintenance required on the PCV system is to replace the PCV valve and/or air filter element in the air cleaner at the intervals specified in the maintenance chart. Replacement involves removing the valve from the grommet in the valve cover and installing a new valve. No attempt should be made to clean an old PCV valve; it should be replaced.