Caution: The fuel system is under pressure. To avoid fuel spillage and risk of injury or fire, turn off the power before disconnecting the fuel lines.
Caution: Do not pinch or block nylon fuel lines, which may cause fuel leakage that could result in fire or injury.
Removal residual fuel pressure
1. Remove the fuel tank filler cap.
2. Remove the fuel pump fuse EF10 located in the engine compartment fuse box.
3. Start the engine and let it stall.
4. Rotate the engine for 10 seconds.
Checking the fuel system
Remove residual pressure in the fuel system.
Connect a fuel pressure gauge. Check for the required fuel pressure (283-324 kPa).
Check the fuel pump by disconnecting the fuel pump connector.
Connect the test lamp between contacts 2 and 3 of the fuel pump connector. When the ignition is turned on, the test lamp should light for 2 seconds.
Inspect the fuel lines for leaks.
Inspect the fuel rail and injectors for leaks.
Check for possible clogging of the fuel filter.
Check for kinks or blockages in the fuel lines.
Check for fuel in the fuel supply lines to the pump.
Inspect the fuel pressure regulator vacuum line for fuel.
Check the fuel for contamination.
Check the fuel pump sensor and fuel coupling hoses for blockages.
Check if the fuel filter in the tank is clogged.
Check the fuel pump relay.
Check the injectors for proper operation by connecting a test lamp between contact 1 of the fuel injector connector and ground, and connecting a test lamp between contact 2 of the fuel injector connector and the "+" terminal of the battery. Turn on the starter. The test lamp should flash. Repeat this check for all fuel injectors.
Measure the resistance of each fuel injector (11.6-12.4 Ohm, as the temperature rises, the resistance will gradually increase).
Replace all injectors with resistance higher than specified.
Check for a possible short to ground in the wires connecting pin 2 of each injector connector to pins A9, A22, A8, A26 of the ECM connector.
Check for a possible short to ground in the wires connecting pin 2 of each injector connector to the ignition switch.
The article was reprinted from the website «ChevyMan»