Fuel System Pressure Release
WARNING: This page is about a different car, the 2003 GMC Sonoma, 2003 GMC Jimmy, 2003 Chevrolet S10 Pickup, and 2003 Chevrolet Blazer. However, it is still accessible from the selected car via links, so may be relevant.
WARNING:
Remove fuel tank cap and release fuel system pressure before servicing any fuel injection-related components. After releasing fuel system pressure, a small amount of fuel may be released when servicing fuel lines, fuel pump or fuel connections. Cover the fuel system components with a shop towel before disconnection. DO NOT allow fuel to contact engine or electrical components.
Turn ignition off. Disconnect negative battery cable. Loosen fuel filler cap. On 4.3L, install Fuel Pressure Gauge (J-34730-1A) on fuel pressure connector of fuel rail. On 2.2L, install Fuel Pressure Gauge (J-34730-FF) on fuel pressure connection. On all models, wrap a shop towel around pressure connection when installing fuel pressure gauge to absorb fuel leakage. Place gauge bleed hose into an approved container. Open bleed valve to release fuel pressure. Drain any fuel remaining in fuel pressure gauge into an approved container.