I know very little about truck engines and I’m interested in getting a diagram or a schematic of the engine for a 1999 GMC Sonoma? Ideally, I’m looking to see if a website might have this.
Autozone.com, in their repair info section it might have what you are looking for.
ALLDATA.com has diagrams, you can get a subscription for your vehicle.
Yes, click on this link to the Auto Zone web site for a lot of that type of information. http://www.autozone.com/shopping/repairGuide.htm When the page displays, choose one of the subject areas and click on it. The Chassis Electrical is actually the engine wiring diagrams (go figure). Some of the subjects are several pages long, so, be sure to scroll down to the ends.
Autozone is OK because it’s free but the information is somewhat limited.