Circuit/System Testing
WARNING: This page is about a different car, the 2009 GMC Sierra, 2009 GMC Cab & Chassis Sierra, 2009 Chevrolet Silverado, and 2009 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
IMPORTANT:
You must perform the Circuit/System Verification before proceeding with Circuit/System Testing.
- Inspect for the following conditions:
- Inadequate fuel in the fuel tanks.
- Fuel smell or leak-Refer to Fuel Leak Diagnosis .
- A plugged air filter collapsed air intake duct
- A restricted exhaust system-Refer to Symptoms - Engine Exhaust .
- Contaminants in fuel-Refer to Contaminants-in-Fuel Diagnosis .
- Install the CH-48027
to the fuel rail service port and crank the engine.
- If more than 5 inches Hg of vacuum was present during cranking, replace the fuel filter and inspect the fuel system restrictions.
- If less than 1 inches Hg of vacuum was present during cranking, go to Fuel System Diagnosis .
- Perform the Engine Compression Test. Refer to Engine Compression Test
.
- If any fuel vapor was emitted during the engine compression test, replace the affected fuel injector.
IMPORTANT: During the replacement of the injectors, inspect the inlet and outlet fittings for corrosion or contamination. Refer to Contaminants-in-Fuel Diagnosis . - Assemble all disconnected components. Prime the fuel system to at least 10 psi. Attempt to start the engine.
- If the engine does start, refer to Fuel System Diagnosis .
- If the engine does not start, refer to Fuel System Diagnosis - High Pressure Side .