Where is the EGR on Cadillac Deville 4.9L?

The EGR valve on a Cadillac Deville with the 4.9L engine is located on the intake manifold. It's usually on the passenger side (right side when sitting in the driver's seat) of the engine, but you'll need to visually inspect the intake manifold to locate it precisely. It's a relatively small valve with a vacuum line connected to it. Because of its location, access might require some maneuvering.