* Haynes or Chilton Repair Manual: These manuals are specifically designed for your vehicle's year and engine and usually include detailed vacuum diagrams. These are your best bet for accuracy. You can find them at most auto parts stores or online retailers like Amazon.
* Online Forums: Websites like ChevyTalk, or other forums dedicated to classic Chevy trucks often have users who might have scanned diagrams or can provide guidance based on similar trucks. Searching for "1986 Chevy 4.3L vacuum diagram" within these forums could yield results. Be sure to specify if you have any specific options (like A/C, power steering, etc.) that might affect the diagram.
* Your local auto parts store: Many auto parts stores (like AutoZone, Advance Auto Parts, O'Reilly Auto Parts) have access to online databases that may include vacuum diagrams. They might be able to print one for you or point you toward a suitable repair manual.
Important Considerations:
* Options: The presence or absence of options like air conditioning, power brakes, cruise control, and even the type of transmission will significantly alter the vacuum routing. Make sure you specify your truck's exact configuration when searching for diagrams.
* Diagram Interpretation: Vacuum diagrams can be complex. If you're not mechanically inclined, it's best to have a repair manual that explains the components and their function to help you interpret the diagram.
Don't rely solely on a generic diagram you might find online. The variations between different 1986 Chevy trucks are substantial enough that a mismatch could cause problems. A repair manual is your best bet for accuracy and safety.
