Diagnostic Aids
WARNING: This page is about a different car, the 2019 GMC Savana 3500, 2019 GMC Savana 2500, 2019 Chevrolet Express 3500, and 2019 Chevrolet Express 2500. However, it is still accessible from the selected car via links, so may be relevant.
An engine cranks but will not run or hard start symptom may exist if air is being drawn into the fuel injection system due to the following conditions:
- Deformed or cut O-rings at the fuel supply line connections
- Improperly seated fuel supply line fittings
- Porous or weathered rubber fuel supply lines
- Fuel filter vent screw not tighten or cross threaded
- Fuel filter not tightened properly