Fuel Pressure Is Low
Use this procedure to troubleshoot a problem with low fuel pressure. Or, use this procedure if one of the following diagnostic codes is active.
Show/hide table
J1939 Code and Description | CDL Code and Description | Comments |
---|---|---|
5578-14
Engine Fuel Delivery Absolute Pressure : Special Instruction |
E489 (1)
Intake Valve Actuation Pressure System Failure |
The prelubrication cycle completed, but the fuel pressure after the secondary filter is lower than expected. |
5580-17
Engine Filtered Fuel Delivery Absolute Pressure : Low - least severe (1) |
E198 (1)
Low Fuel Pressure |
The fuel pressure after the secondary fuel filter is lower than expected while the engine is running. |
5580-18
Engine Filtered Fuel Delivery Absolute Pressure : Low - moderate severity (2) |
E198 (2)
Low Fuel Pressure |
The fuel pressure after the secondary fuel filter is lower than expected while the engine is running. |
Show/hide table
Associated Codes | ||
---|---|---|
J1939 Code | CDL Code | Troubleshooting Procedure |
95-0 | E390 (3) | Troubleshooting, "Fuel Filter Is Restricted" |
95-15 | E390 (1) | Troubleshooting, "Fuel Filter Is Restricted" |
95-16 | E390 (2) | Troubleshooting, "Fuel Filter Is Restricted" |
1381-17 | E2172 (1) | Troubleshooting, "Fuel Transfer Pump Inlet Pressure Is Low" |
1382-15 | E1129 (1) | Troubleshooting, "Fuel Filter Is Restricted" |
1382-16 | E1129 (2) | Troubleshooting, "Fuel Filter Is Restricted" |
5417-15 | E1569 (1) | Troubleshooting, "Clean Fuel Module - Test" |
5417-16 | E1569 (2) | Troubleshooting, "Clean Fuel Module - Test" |
Show/hide table
Troubleshooting Test Steps | Values | Results |
---|---|---|
1. Check for Codes A. Apply electrical power to the engine. B. Connect Cat® Electronic Technician (ET) to the service tool connector. C. Look for active codes that are associated with the system for the event code. |
Codes |
Result: An associated code is active. Repair: Troubleshoot any associated codes before continuing with this test. Result: A code is active or logged. Proceed to Test Step 2. |
2. Check the Fuel Tank Level A. Remove electrical power from the engine. B. Inspect the fuel level to make sure that the tank level is not too low. |
Fuel Level |
Result: The fuel level is NOT low. Proceed to Test Step 3. Result: The fuel level is low. Repair: Add fuel to the fuel tank. Proceed to Test Step 12. |
3. Check for Fuel Leaks A. Remove electrical power from the engine. B. Inspect the low-pressure fuel system for leaks. C. Check the low-pressure fuel system connections to make sure that the connectors are properly torqued. D. Check the fuel filter drain plug fittings. |
Fuel Tank |
Result: A fuel leak was found. Repair: Repair the cause of the fuel leak. Replace parts as necessary. Proceed to Test Step 12. Result: There are no fuel leaks. Proceed to Test Step 4. |
4. Prime the Fuel System A. Use the manual priming switch to prime the fuel system. Refer to the Original Equipment Manufacturers (OEM) procedure to prime the fuel system. |
Fuel System Primed |
Result: The fuel system was priming sequence was completed. Proceed to Test Step 5. |
5. Check the Fuel Pressure Sensor A. Apply electrical power to the engine. B. Connect to Cat ET. C. Monitor the following parameter in the status screen: - "Fuel Pressure" |
Fuel Pressure |
Result: The fuel pressure reading is For an E198 or 5580 code, proceed to Test Step 6. For a 5578 code, proceed to Test Step 9. Result: The fuel pressure reading is NOT Repair: Replace the fuel pressure sensor. Proceed to Test Step 12. |
Show/hide table
Illustration 1 | g03810811 |
Typical Fuel Filter (1) Starting priority valve (2) System pressure regulator |
Show/hide table
Troubleshooting Test Steps | Values | Results |
---|---|---|
6. Check the Low-Pressure Fuel System Pressure Regulator A. Remove electrical power from the engine. B. Remove the low-pressure fuel system pressure regulator from the secondary fuel filter auxiliary manifold. Refer to D&A manual for proper procedure. C. Check the low-pressure fuel system pressure regulator by actuating the spool within the cartridge assembly. |
Low-Pressure Fuel System Pressure Regulator |
Result: The low-pressure fuel system pressure regulator moves freely through the full travel. Reinstall the low-pressure fuel system pressure regulator. Proceed to Test Step 7. Result: The low-pressure fuel system pressure regulator does NOT freely move through the full travel. Repair: Replace the low-pressure fuel system pressure regulator. Proceed to Test Step 12. |
Show/hide table
Illustration 2 | g03813358 |
Pressure relief valve |
Show/hide table
Troubleshooting Test Steps | Values | Results |
7. Check the Fuel Transfer Pump Pressure Relief Valve A. Remove electrical power from the engine. B. Remove the fuel transfer pump pressure relief valve from the fuel transfer pump. Refer to D&A manual for proper procedure. C. Check the fuel transfer pump pressure relief valve by actuating the spool within the cartridge assembly. |
Fuel Transfer Pump Pressure Relief Valve |
Result: The fuel transfer pump pressure relief valve moves freely through the full travel. Reinstall the fuel transfer pump pressure relief valve. Proceed to Test Step 8. Result: The fuel transfer pump pressure relief valve does NOT freely move through the full travel. Repair: Replace the fuel transfer pump pressure relief valve. Proceed to Test Step 12. |
Show/hide table
Illustration 3 | g03825758 |
Injector cooling back-pressure regulator (3) Pressure regulator |
Show/hide table
Troubleshooting Test Steps | Values | Results |
---|---|---|
8. Check the Injector Backpressure Regulator A. Remove electrical power from the engine. B. Remove Injector backpressure regulator from the low-pressure injector cooling manifold in the fuel cooling rail. Refer to D&A manual for proper procedure. C. Check the Injector backpressure regulator by actuating the spool within the cartridge assembly. |
Injector Backpressure Regulator |
Result: The Injector backpressure regulator moves freely through the full travel. Reinstall the Injector backpressure regulator. Proceed to Test Step 11. Result: The Injector backpressure regulator does NOT freely move through the full travel. Repair: Replace the Injector backpressure regulator. Proceed to Test Step 12. |
9. Check the Starting Priority Valve A. Remove electrical power from the engine. B. Remove the starting priority valve from the secondary fuel filter head. Refer to D&A manual for proper procedure. C. Check the starting priority valve operation by actuating the spool within the cartridge assembly. Note: For starting priority valve location, refer to Illustration 1. |
Starting Priority Valve |
Result: The starting priority valve moves freely through the full travel. Reinstall the starting priority valve. Proceed to Test Step 10. Result: The starting priority valve does NOT freely move through the full travel. Repair: Replace the starting priority valve. Proceed to Test Step 12. |
10. Check the Fuel Transfer Pump Pressure Relief Valve A. Remove electrical power from the engine. B. Remove the fuel transfer pump pressure relief valve from the fuel transfer pump. Refer to D&A manual for proper procedure. C. Check the fuel transfer pump pressure relief valve by actuating the spool within the cartridge assembly. Note: For fuel transfer pump pressure relief valve location, refer to Illustration 2. |
Fuel Transfer Pump Pressure Relief Valve |
Result: The fuel transfer pump pressure relief valve moves freely through the full travel. Reinstall the fuel transfer pump pressure relief valve. Proceed to Test Step 11. Result: The fuel transfer pump pressure relief valve does NOT freely move through the full travel. Repair: Replace the fuel transfer pump pressure relief valve. Proceed to Test Step 12. |
11. Replace the Fuel Transfer Pump A. Remove electrical power from the engine. B. Replace the fuel transfer pump. |
Fuel Transfer Pump |
Result: The transfer pump was replaced. Proceed to Test Step 12. |
12. Check for Codes A. Start the engine and operate at high idle for 1 minute. B. Look for active or logged diagnostic codes. |
Diagnostic Codes |
Result: No codes present. Return to service. |
If the procedure did not correct the issue, contact your Cat dealer Technical Communicator (TC). For further assistance, your TC can confer with the Dealer Solutions Network (DSN).
Caterpillar Information System:
C175-16 Locomotive Engine Fuel Control - Test
C12.9 Marine Engines Engine Support (Front) - Remove and Install
G3512 Generator Set Engines Speed/Timing - Test
Coolant Drain and Vacuum Fill Procedure For Certain C9.3 Through C18 Tier 4 Engines {0708, 1350, 1354, 1377} Coolant Drain and Vacuum Fill Procedure For Certain C9.3 Through C18 Tier 4 Engines {0708, 1350, 1354, 1377}
Cat® Reman Announces Engine Option for Certain 3406C Marine Engines {1000} Cat® Reman Announces Engine Option for Certain 3406C Marine Engines {1000}
C175-16 Locomotive Engine Oil Pressure Is Low
3512E Engines Venturi Tube - Remove and Install
C3.3 Industrial Engine Connecting Rod - For Use With Spheroidal Graphite Iron (SGI) Crankshaft
C3.3 Industrial Engine Main Bearing Journal - Spheroidal Graphite Iron (SGI) Crankshaft
C4.4 Generator Sets Turbocharger
C3.3 Industrial Engine Connecting Rod Bearing Journal - Spheroidal Graphite Iron Crankshaft
C7.1 Marine Engine Engine Oil Filter Base - Remove and Install
TR35 Railway Transmission Capacities (Refill)
C12.9 Marine Engines Fuel Injection Pump - Remove and Install
TR35 Railway Transmission Transmission Cooling System
C175 Tier 4 Final Engines for Off-Highway Trucks Data Link Configuration Status - Test
C175 Tier 4 Final Engines for Off-Highway Trucks DEF Control Module Temperature Is High
TR35 Railway Transmission Lifting and Tying Down the Transmission
C175 Tier 4 Final Engines for Off-Highway Trucks DEF Does Not Purge
C175 Tier 4 Final Engines for Off-Highway Trucks DEF Pump - Replace
G3512 EPA Emergency and Non-Emergency Standby Generator Sets Sensors and Electrical Components
Valve Stem Seals on Certain C1.1,C1.5, and C2.2 Engines {1100} Valve Stem Seals on Certain C1.1,C1.5, and C2.2 Engines {1100}
G3512 EPA Emergency and Non-Emergency Standby Generator Sets Before Starting Engine
XQ60 Rental Generator Set Model View Illustrations