The computer in a 1999 Chevy G-Van, also known as the Powertrain Control Module (PCM) or Engine Control Module (ECM), is typically located
under the hood, near the firewall. However, the exact location can vary slightly depending on the specific engine and other options on the van. It's often secured to a bracket or attached to the inner fender.
To find it, look for a relatively large, black box with numerous wiring harnesses connected to it. It might have labels or markings indicating its function. A service manual for your specific 1999 Chevy G-Van will provide the most accurate location information.
