* Repair Manual: A factory service manual (FSM) or a Haynes/Chilton repair manual for a 2004 Chevrolet Trailblazer will have the most comprehensive diagrams, including wiring diagrams, engine block diagrams, and component layouts. These manuals are available online (often as PDFs) or from auto parts stores. Search for "2004 Chevrolet Trailblazer repair manual" to find options. Specify the engine size (4.2L I6 or 5.3L V8) if you know it, as the diagrams will differ.
* Online Parts Diagrams: Websites like AutoZone, Advance Auto Parts, and others selling auto parts often have online parts diagrams. You'll need to select your year, make, model, and engine size to view the diagrams. These are usually less detailed than a repair manual but are good for identifying parts.
* Google Images: A general Google Image search for "2004 Trailblazer [engine size] engine diagram" might yield some results, but the quality and accuracy can vary widely. This is a less reliable method.
* YouTube: Some mechanics post videos showing engine components, which can act as a visual aid.
Important Note: The engine diagram you need will depend on your specific problem. If you are troubleshooting a mechanical issue, a general engine diagram might not be sufficient. You may need a specific diagram showing the fuel system, ignition system, cooling system, etc. Clearly stating your problem will help you find the most relevant diagram.
