PIN 2826604 - Caterpillar

Use this procedure in order to troubleshoot a low fuel rail pressure. Also, use this procedure if one of the following event codes is active.
Table 1
Event Code
J1939 Code and Description Conditions which Generate this Code System Response
157-17 Engine Injector Metering Rail #1 Pressure : Low - least severe (1) The fuel rail pressure is below the trip point pressure for the programmed delay time. The code is logged.
157-18 Engine Injector Metering Rail #1 Pressure : Low - moderate severity (2) The code is logged.
Engine power is derated. Probable Causes
Diagnostic codes and event codes
Low-pressure fuel system
High-pressure fuel rail leakage
Fuel rail pressure sensor problem
Fuel control valve problemRecommended Actions
Table 2
Troubleshooting Test Step Value Result
1. Check for Codes
A. Connect Caterpillar Electronic Technician (ET) to the service tool connector. Refer to Troubleshooting, "Electronic Service Tools", if necessary.
B. Download the "Product Status Report" from the engine ECM before performing any troubleshooting or clearing diagnostic trouble codes.
C. Determine if the diagnostic trouble code that directed to this procedure is present.
D. Look for active diagnostic codes that are associated with the system for the event code that directed to this procedure.
157-17 or 157-18
Result: An associated code is present.
Repair: Troubleshoot any associated codes before continuing with this test.
Result: A 157-17 or 157-18 code is present.
Proceed to the next step.
Result: No active codes
STOP
2. Check the Low Pressure Fuel System
A. Use Cat ET to monitor the value for the "Fuel Pressure (absolute)" parameter while you operate the engine. Monitor the parameter at all engine speeds.
B. Ensure that the "Fuel Pressure (absolute)" parameter is greater than 250 kPa (36 psi) (gauge) at low engine idle and that the pressure is at least 450 kPa (65 psi) (gauge) with the engine at high engine idle.
At rated engine speed and load, the optimum performance and durability of the high-pressure fuel pump is realized if the inlet pressure for the fuel control valve is maintained at 650 kPa (94 psi).
Pressure
Result: The "Fuel Pressure (absolute)" is OK.
Repair: Proceed to the next step.
Result: The "Fuel Pressure (absolute)" is NOT OK.
Repair: Refer to Troubleshooting, "Fuel Pressure Is Low (Fuel Transfer System)" in order to troubleshoot the symptom.
If the problem is not resolved, proceed to the next step.
3. Check for High-pressure Fuel Rail Leakage
A. Refer to Troubleshooting, "Fuel Rail Pressure Leakage Is High".
B. Refer to Systems Operation/Testing and Adjusting, "Injector Bypass Fuel Flow - Test".
Leak
Result: An excessive leak was not found.
Proceed to the next step.
Result: An excessive leak was found and repaired.
If the problem is not resolved, proceed to the next step.
4. Check the Fuel Rail Pressure Sensor
A. With the engine shutdown, use Cat ET to check the value for the "Fuel Rail Pressure (absolute)" parameter. After the engine has been shut down for 10 minutes, the "Fuel Rail Pressure (absolute)" will be less than 5,000 kPa (725 psi) (gauge).
If the pressure is not less than 5,000 kPa (725 psi) (gauge) after 10 minutes, vent the pressure from the fuel system. Refer to Systems Operation/Testing and Adjusting, "Fuel Rail Pressure - Release" for information.
Rail
pressure
Result: The sensor