To find it, you'll need:
1. A Repair Manual: This is the best resource. It will have a diagram clearly showing the location of each spark plug.
2. An Online Diagram: Search for "2002-2007 Buick Rendezvous 3.4L V6 spark plug location diagram" (adjust the years to match your Rendezvous's year). Several websites offer such diagrams. Be cautious of their accuracy; always double-check with your vehicle's manual.
3. Visual Inspection: With the engine cool and the ignition off, carefully observe the top of the engine. The spark plug wires or coils will often be easily identifiable, allowing you to trace the #1 wire to its corresponding plug.
Important Note: Before working on your engine, always disconnect the negative terminal from your battery to prevent electrical shock and damage.