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Home >> Alfa Romeo >> 2019 >> Giulia Base, AWD >> Repair and Diagnosis >> Engine Performance >> System >> 2.0L - DTCS B1810-00 To P0111-00 >> DTC Troubleshooting >> P0087-00-Fuel Rail/System Pressure - Too Low Bank 1 >> Diagnostic Test

Diagnostic Test

  1. CHECK FOR ANY SERVICE BULLETINS OR PCM SOFTWARE UPDATES 
    1. Check for any applicable Service Bulletins or Flash updates related to the DTC.

      Are there any applicable Service Bulletins or Flash updates?

      Yes 

      No 

      • Go To  2
  2. CHECK FOR AN ACTIVE DTC 
    NOTE:

    Verify there is fuel in the fuel tank before continuing with this test procedure.

    1. With the scan tool, read DTCs in all Electronic Control Units (ECUs) and record on the repair order.
    2. For future reference, with the scan tool, run and save a vehicle Scan Report and all related recorded data.
    3. With the scan tool, erase all DTCs.
    4. Turn the ignition off for a minimum of 10.0 seconds.
    5. Turn the ignition on.
    6. Using the When Monitored and Set Conditions above and recorded data, operate the vehicle in the conditions that set the DTC.
    7. With the scan tool, read DTCs.

      Did the DTC return?

      Yes 

      • Go To  3

      No 

  3. CHECK THE HIGH PRESSURE FUEL SYSTEM FOR A SIGNS OF A LEAK 
    NOTE:

    Do not run the engine when inspecting the high pressure fuel system for leaks. The system pressure can be extremely high.

    1. Visually inspect for signs of fuel leaks at the high pressure fuel tube and Fuel Injectors.

      Are any leaks present?

      Yes 

      • If the leak appears to be at the high pressure fuel tube, verify that the tube is torqued correctly. If the torque is correct, replace the high pressure fuel tube in accordance with the Service Information. If the leak appears to be at a Fuel Injector, perform the appropriate repair in accordance with the Service Information.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Go To  4
  4. CHECK THE FUEL RAIL PRESSURE SENSOR READING 
    1. Start the engine and allow it to idle.
      NOTE:

      The fuel rail pressure should be above approximately 2000 psi.

    2. With the scan tool, monitor the fuel rail pressure reading.
      NOTE:

      If only one of the pressure signal readings is low and the other is reading normal, the performance/rationality DTC should be present. Diagnose the Fuel Rail Pressure Sensor rationality fault for the sensor signal that is reading low before continuing with this test procedure.

      Is the fuel rail pressure value reading below specification?

      Yes 

      • Go To  5

      No 

  5. CHECK THE LOW FUEL PRESSURE SYSTEM FOR PROPER OPERATION 
    1. Perform the CHECKING THE LOW PRESSURE FUEL SYSTEM test procedure. Refer to CHECKING THE LOW PRESSURE FUEL DELIVERY SYSTEM ..

      Were any issues found?

      Yes 

      No 

      • Go To  6
  6. CHECK FOR HIGH RESISTANCE IN THE (F851) 5-VOLT SUPPLY CIRCUIT 
    1. Disconnect the Fuel Rail Pressure (FRP) Sensor 1 harness connector.
    2. Disconnect the PCM C2 harness connector.
    3. Measure the resistance of the (F851) 5-Volt Supply circuit between the FRP Sensor harness connector and the PCM C2 harness connector.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  7

      No 

      • Repair the high resistance in the (F851) 5-Volt Supply circuit.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  7. CHECK FOR HIGH RESISTANCE IN THE (K917) SENSOR GROUND CIRCUIT 
    1. Measure the resistance of the (K917) Sensor Ground circuit between the FRP Sensor harness connector and the PCM C2 harness connector.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  8

      No 

      • Repair the high resistance in the (K917) Sensor Ground circuit.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  8. CHECK FOR HIGH RESISTANCE IN THE (K366) FUEL QUANTITY SOLENOID 12 VOLT SUPPLY CIRCUIT 
    1. Turn the ignition off.
    2. Disconnect the Fuel Quantity Solenoid harness connector.
    3. Disconnect the PCM-1 C2 harness connector.
    4. Measure the resistance of the (K366) Fuel Quantity Solenoid 12 Volt Supply circuit between the PCM C2 harness connector and the Fuel Quantity Solenoid harness connector.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  9

      No 

      • Repair the (K366) Fuel Quantity Solenoid 12 Volt Supply circuit for an open or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  9. CHECK FOR HIGH RESISTANCE IN THE (K365) FUEL QUANTITY CONTROL CIRCUIT 
    1. Measure the resistance of the (K365) Fuel Quantity Control circuit between the PCM C2 harness connector and the Fuel Quantity Solenoid harness connector.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  10

      No 

      • Repair the (K365) Fuel Quantity Control circuit for an open or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  10. REPLACE THE FUEL RAIL PRESSURE SENSOR AND RETEST FOR DTC 
    1. Replace the Fuel Rail Pressure Sensor in accordance with the Service Information.
    2. Connect the FRP Sensor and PCM C2 harness connectors.
    3. Turn the ignition on.
    4. With the scan tool, erase DTCs
    5. Using the When Monitored and Set Conditions above and recorded data, operate the vehicle in the conditions that set the DTC.
    6. With the scan tool, read DTCs.

      Did the DTC return?

      Yes 

      No 

      • Replacing the Fuel Rail Pressure Sensor repaired the fault.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .