Where is the location of ecm in a 1986 sierra gmc 305 engine?

The ECM (Engine Control Module) in a 1986 GMC Sierra with a 305 engine is typically located under the hood, on the passenger side fender well. However, its exact position can vary slightly depending on specific trim levels and options. It's usually attached to the inner fender apron or firewall area. You might need to look closely and possibly remove some sound deadening material to find it. It's a fairly small, rectangular black box.