Where is Egr located on 1991 buick park avenue 3.8L code L engine?

The EGR valve on a 1991 Buick Park Avenue with the 3.8L L-code engine is located on the intake manifold. It's usually on the passenger side (right side as you're sitting in the driver's seat) of the engine, near the back. However, the exact position can vary slightly depending on the specific manifold casting. You'll need to visually inspect the intake manifold to locate it. Look for a small, usually rectangular valve with a vacuum line connected to it.