GM: Electra/Park Avenue/Ninety-Eight 1990-1993

Relieving Fuel System Pressure

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PREFERRED METHOD



  1. Disconnect the negative battery cable.
  2.  
  3. Loosen the fuel filler cap to relieve fuel tank vapor pressure.
  4.  
  5. Obtain fuel pressure valve J 34730-1 or equivalent. Wrap a shop towel around the fittings while connecting the tool to prevent fuel spillage.
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  7. Connect the tool to the fuel pressure relief connection at the fuel rail.
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  9. Install a bleed hose into an approved container and open the valve to bleed the system pressure.
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  11. Install the fuel filler cap.
  12.  

ALTERNATE METHOD





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Fig. Fig. 1 Fuel pump relay location in the relay center under the right side of the instrument panel. Some relays may vary slightly between models, but the fuel pump relay is in the same position throughout the C body line



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Fig. Fig. 2 Oil pressure sending unit location on the lower right side of the engine behind the camshaft sensor. The unit itself may vary between engine applications

  1. If the above tool is not available, you can run the engine out of gas by cutting off the voltage to the fuel pump and running the engine until all available fuel is spent.
  2.  
  3. To accomplish this, remove the fuel pump relay and disconnect the oil pressure sending unit. The oil pressure sending unit is used as a backup path for voltage to take (as long as there is sufficient oil pressure) if the relay were to fail, so be sure to disconnect it also, or the pump will run and the engine won't run out of fuel; refer to the appropriate wiring schematics in for further explanation. The relay is in the relay center under the right side of the instrument panel, and the oil pressure sending unit is on the lower right side of the engine behind the camshaft sensor.
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  5. Start the engine and run until it stalls from lack of fuel.
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  7. Disconnect the negative battery cable and proceed with work on the fuel system.
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  9. Don't forget to install the fuel pump relay and connect the oil pressure sending unit when the job is done.
  10.  

 
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