Vacuum Control Valve (VCV)
- A 2-port valve may be in open or closed position when engine is cold, but should reverse when engine is warmed to operating temperature.
- For 3-port valves, with a cold engine, passage "A" to "B" should be closed and passage "A" to "C" should be open. See Fig 1. With engine at normal operating temperature, the VCV should be open between "A" and "B" and closed between "A" and "C".
Courtesy of FORD MOTOR CO.
- For the 4-port valve, check "A[I1]" to "B[I1]" and "A[I2]" to "B[I2]" separately. See Fig 1. A 4-port valve may be in open or closed position when engine is cold, but should reverse when engine is warmed to operating temperature. If these conditions are not met, replace the valve.