FB3 - Fuel Pressure Regulator Diaphragm Condition

WARNING: Fuel in the fuel system remains under high pressure even when the engine is not running. To avoid injury or fire, release the fuel pressure from the fuel system before disconnecting any fuel line.

To release fuel pressure refer to Service and Repair/Fuel System Pressure Relief Procedure.

Fuel Pressure Test Setup:

^ Install Rotunda Fuel Pressure Tester 014-00748 or equivalent with EFI Test Adapter D87C-9974-A in the fuel line between the fuel filter and fuel rail, with its main valve open and its drain valve closed.

^ Start the engine and run for 10 seconds.

^ Stop the engine and wait 10 seconds.

^ Start the engine again and run for 10 seconds.

^ Stop the engine and remove the vacuum hose from the pressure regulator.

^ Examine the vacuum port in the pressure regulator for evidence of fuel leakage through the diaphragm.

^ Is the vacuum port OK?

YES -- Go to FB4. FB4 - Fuel Pressure Regulator Leak Down Check

NO -- Replace the fuel pressure regulator and rerun Fuel Pressure Test.