LBZ, LLY, MIL/SES Light On, DTC P0087 - Fuel Rail Pressure (FRP) Too Low, Lack of Performance, No Power, Engine Runs Rough, No Start (Diagnose Fuel System Components)

Some customers may comment on an illumination of the MIL/SES with one or more of the following symptoms:

Upon further investigation, the technician may find DTC P0087- Fuel Rail Pressure (FRP) Too Low stored in the ECM.

A ceramic high pressure valve ball fracture inside the fuel injection pump may lead to internal pump damage resulting in low fuel rail pressure. This condition may contaminate the common fuel rails and fuel injectors with debris. The fuel injection pump may operate, but with reduced output flow.

A high pressure valve fracture may cause the fuel injection pump cup plug (1) to come out, resulting in a no start condition and a possible fluid leak.

There are several bulletin resources available in the Electronic Service Information System (SI) that can provide the technician with information on diagnosis and repair of the fuel system. Some of the bulletins available in SI include:

Caution:  Remove the fuel tank cap and relieve the fuel system pressure before servicing the fuel system in order to reduce the risk of personal injury. After you relieve the fuel system pressure, a small amount of fuel may be released when servicing the fuel lines, the fuel injection pump, or the connections. In order to reduce the risk of personal injury, cover the fuel system components with a shop towel before disconnection. This will catch any fuel that may leak out. Place the towel in an approved container when the disconnection is complete.

Important: Make sure you clock in and record the actual repair order clock time when completing this repair. A copy of the repair order and a print out of the Engine Data 1 snapshot along with the fuel rail pressure graph may be required. Failure to provide copies of this information may cause your warranty claim to be rejected.

Start by diagnosing the fuel system components by referring to Fuel System Diagnosis in SI.

If the vehicle starts and runs, verify that there are no fuel pump inlet restrictions on the supply side by inspecting for kinked fuel lines or a clogged fuel filter. If the vehicle does not exhibit any fuel supply restrictions or the engine does not start, proceed with the following diagnosis:

Tighten
Tighten the fuel pressure relief valve to 100 N·m (74 lb ft).

1. Start and idle the engine to normal operating temperatures.
2. Using a Tech®2 scan tool, build the vehicle information.
3. Select F2: Special Functions.
4. Select F2: Fuel Systems.
5. Select F3: Fuel Pressure Control.
6. Using the Tech®2 scan tool, increase the fuel rail pressure to 100  MPa (14,503 psi) for desired fuel rail pressure.

Tip
You will have to manually exit the snapshot after 1 minute of recording.

7. Select quick snapshot (located on the bottom screen of the Tech®2 scan tool) and record Engine Data 1 for one minute. When the snapshot data has been recorded, exit to the Main Menu, then power down and disconnect the Tech 2® from the vehicle. The snapshot should capture the desired fuel rail pressure versus the actual fuel rail pressure in Engine Data 1.

Important: Make sure you select the correct vehicle snapshot when downloading the information to the TIS Software.

8. Download the snapshot data to the computer using the TIS Software.




8.1.	Launch TIS2WEB and enter the main screen, select Snapshot (Snap) as shown in the graphic above with the arrow.





8.2.	Click on Start Snapshot (1).





8.3.	Select the Upload from Handheld button to launch the device selection screen in TIS as shown above.

8.4.	Select the current snapshot that you just recorded. Then click "OK." The snapshot data should upload to the computer.





8.5.	Print the engine data snapshot as shown above. Return a printed copy of this Engine Data 1 snapshot with the old parts.

Important: Printing a line graph is currently not an available feature in the TIS software. You will have to take a screen print of the graph from TIS and paste the graph into Microsoft® (MS) Paint or Word programs.

9. Graph and print the desired fuel rail pressure versus the actual fuel rail pressure using TIS software following the directions below:




9.1.	Click on "Display 6 Graphs" as shown in the graphic above.





9.2.	Graph Parameters, first select "Actual Fuel Rail Pressure" from the bottom data file this will become the top red line graph value (1).





9.3.	Select the next green line graph (1) and then click on the "Desired Fuel Rail Pressure" from the bottom data file.





9.4.	Change the first two Min Y Axis Values (1) from 1.0 to 97.





9.5.	Change the second two Max Y Axis Values (1) from 65535.0 to 103.

9.6.	Click OK to display graph.

9.7.	Copy the graph by pushing down on the Control (Ctrl) and Print Screen (Print Scrn) buttons at the same time on your computer key board.

9.8.	Open MS Paint and paste the line graph into Paint using the directions below:





9.8.1.

Click on "Start" (located in lower left corner of the computer screen) (1).

9.8.2.

Select "Programs" (2) or "All Programs.".

9.8.3.

Select "Accessories" (3).

9.8.4.

Select "Paint" (4) and click on it.





9.8.5.

From the top left side toolbar, click on" Edit ' in the Paint screen and select "Paste". Click on "Paste" and your line graph should appear as shown in the graphic above. If it does not appear you will have to go back to the TIS screen with the line graph and repeat Step 9.7 and Step 9.8.5.

9.8.6.

Click on "File" (located in the upper left of the computer screen, under Untitled Paint application).





9.8.7.

Select "Page Setup" and click as shown above.





-	Under Orientation, click "Landscape"(1).

-	Under Scaling, click "Fit to" (2).

-	Under Scaling, enter "1 by 1" pages (3).

-	Click on OK (4).





9.9.	Click on "File" (1) (located in the upper left of the computer screen, under Untitled Paint application).

9.10.

Select "Print" and click. You should have a paper copy of the line graph to send back with the old parts being returned.

Example of Good Fuel Injection Pump Which Shows less than 3 MPa (435 psi) peak-to-peak fluctuation





Note: The graph reading above is an example of a good pump.

Example of Bad Fuel Injection Pump Which Shows more than 3 MPa (435 psi) peak-to-peak fluctuation





Note: The graph reading above is an example of a bad pump.

10. Compare your graph to the examples above to determine if the fuel injection pump is good or bad. The straight line is the desired fuel rail pressure (1) and the varying line is your actual fuel line pressure (2).

•	If less than 3 MPa (435 psi), peak-to-peak pressure fluctuations are observed, refer to normal SI diagnostics.

•	If more than 3 MPa (435 psi), peak-to-peak pressure fluctuations are observed or there is evidence that the fuel injection pump cup plug is missing, replace the fuel injection pump, both common fuel rails, all eight fuel injectors. and flush the fuel system using Steps 11-19.

11. Replace the fuel injection pump assembly. Refer to Fuel Injection Pump Replacement in SI.
12. Replace the left and right fuel injector rails. Refer to Fuel Rail Assembly Replacement in SI.
13. Replace all eight fuel injectors. Refer to Fuel Injector Replacement in SI.
14. Reprogram injector flow rates. Refer to Fuel Injector Flow Rate Programming in SI.
15. Flush all high pressure fuel lines of debris. Refer to Fuel System Cleaning in SI.
16. Replace the fuel filter. Refer to Fuel Filter Replacement in SI.
17. Prime the fuel system. Refer to System Priming in SI.
18. Start the engine and inspect for fuel leaks. Refer to Fuel Leak Diagnosis in SI.
19. Clear any codes and verify that the condition has been corrected.

Important: Some vehicles may require the removal of the turbo when replacing the fuel injection pump.

Important: Make sure you clock in and record the actual repair order clock time when completing this warranty repair. The old fuel injection pump must include a print out of the Engine Data 1 snapshot along with the data line graph showing the desired fuel rail pressures versus the actual fuel rail pressures. If proper documentation is not found with the old parts or you do not show actual repair order clock time, your warranty claim may be denied.

For vehicles repaired under warranty, use: