Diagnostic Aids
WARNING: This page is about a different car, the 2008 GMC Sierra, 2008 GMC Cab & Chassis Sierra, 2008 Chevrolet Silverado, and 2008 Chevrolet Cab & Chassis Silverado. 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:
- Fuel contamination-Refer to Contaminants-in-Fuel Diagnosis .
- 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 tighten properly