Visual Inspection
WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Savana, 2003 Chevrolet Silverado, and 2003 Chevrolet Chevy Express. However, it is still accessible from the selected car via links, so may be relevant.
Visually inspect all electrical wiring. Look for chafed, stretched, cut or pinched wiring. Ensure electrical connectors fit tightly and are not corroded. Ensure vacuum hoses are properly routed and not pinched or cut. If necessary, see VACUUM DIAGRAMS - EXPRESS & SAVANA article or VACUUM DIAGRAMS - SIERRA & SILVERADO article to verify routing and connections. Inspect air induction system for possible vacuum leaks.