Circuit/System Verification
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- Inspect the fuel system for damage or external leaks before proceeding.
- Verify that adequate fuel is in the fuel tank before proceeding.
- The fuel pump relay may need to be commanded ON a few times in order to obtain the highest possible fuel pressure.
- Ignition ON, command the fuel pump relay ON with a scan tool. You should hear the fuel pump turn ON and OFF.
- If the fuel pump does not operate, refer to Fuel Pump Electrical Circuit Diagnosis .
- Ignition OFF, all accessories OFF, install the CH-48027 . See Special Tools . Refer to Fuel Pressure Gage Installation and Removal .
- Ignition ON, command the fuel pump relay ON with a scan tool. Verify the fuel pressure is between 345-414 kPa (50-60 psi) and remains steady for 5 minutes.
IMPORTANT: