Where is the location of engine computer a 1997 Cadillac Deville?

The engine control module (ECM), often called the engine computer, in a 1997 Cadillac DeVille is typically located under the hood, near the firewall, often attached to the inner fender well. It's usually a fairly large, rectangular black box. However, the exact placement can vary slightly depending on specific options and trim levels. A detailed look at a wiring diagram or your owner's manual might give a more precise location if needed.