C13 Engines for Caterpillar Built Machines Caterpillar

Fuel Pressure Is Low

Usage:

System Operation Description:

Note: The E198 code may activate when the water separator is being drained. Disregard the code and toggle the keyswitch to clear the code.

Use this procedure to troubleshoot a low fuel pressure. Use this procedure if one of the following event codes is active. Refer to Troubleshooting, "Event Codes" for information about event codes. For information on the engine monitoring system, refer to Troubleshooting, "Engine Monitoring System".

Note: Some of the following codes may not be applicable for certain applications.

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Table 1

CDL Code	Code Description	Comments
E198 (1)	Low Fuel Pressure	The code is logged.
E198 (2)	Low Fuel Pressure	The code is logged. The engine power is derated. The Electronic Control Module (ECM) will illuminate the action lamp.

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Contact with high pressure fuel may cause fluid penetration and burn hazards. High pressure fuel spray may cause a fire hazard. Failure to follow these inspection, maintenance and service instructions may cause personal injury or death.

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Table 2
Troubleshooting Test Steps	Values	Results
1. Determine the Code A. Connect Cat^® Electronic Technician (ET) to the service tool connector. Refer to Troubleshooting, "Electronic Service Tools", if necessary. B. Download the "Warranty Report" from the engine ECM before performing any troubleshooting or clearing diagnostic trouble codes. C. Determine if a diagnostic trouble code is present or an associated code is present.	Codes	Result: An E198 code is present. Proceed to Test Step 2. Result: An associated code is present. Repair: Troubleshoot the associated code. Refer to the proper troubleshooting procedure. STOP
2. Check the Fuel Level in the Tank A. Visually inspect the fuel level in the fuel tank. Ensure that the fuel tank contains enough fuel to operate the engine. B. Ensure that the fuel supply valve (if equipped) is in the full OPEN position.	Fuel Level	Result: The fuel level is OK. Proceed to Test Step 3. Result: The fuel level is not OK. Repair: Fill the tank. Verify that the problem has been resolved. If the problem is not resolved, proceed to Test Step 3.
3. Inspect the Fuel System for Leaks A. Perform a visual inspection of the fuel system. Verify that there are no fuel leaks. Inspect the fuel lines from the fuel transfer pump to the secondary fuel filter base for restrictions. Refer to Systems Operation/Testing and Adjusting, "Fuel System - Inspect" for additional information.	Fuel System	Result: No leaks were found. Proceed to Test Step 4. Result: Leaks were found in the fuel system. Repair: Repair the leaks. Verify that the problem is resolved. If the problem is not resolved, proceed to Test Step 4.

Note: Cold weather adversely affects the characteristics of the fuel. Refer to the engine Operation and Maintenance Manual for information on improving the characteristics of the fuel during cold-weather operation.

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Table 3
Required Tooling for Fuel Pressure Sensor
8t-7860 Connector
110-6349 Fitting As
8t-0855 Pressure Gauge
6v-3990 Coupler

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Illustration 1	g06140091
C13 - C18 Engines (1) Fuel temperature sensor (2) Fuel sampling port (3) Fuel pressure sensor (4) Fuel filter base

Note: Do not use location (2) for measuring the fuel pressure. Follow the steps below.

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Table 4
Troubleshooting Test Steps	Values	Results
4. Check the Fuel Pressure Sensor A. Record the fuel pressure from Cat ET. Record the value in Table 5. B. Remove the fuel pressure sensor . C. Install a 8t-7860 Connector into the port of the pressure sensor . D. Install the 110-6349 Fitting As onto the 8t-7860 Connector. E. Install a 8t-0855 Pressure Gauge onto a 6v-3990 Coupler. F. Install the 6v-3990 Coupler onto the 110-6349 Fitting As. G. Record the fuel pressure from Cat ET and on the pressure gauge. Record the data in Table 5.	Pressure Sensor	Result: The gauge value of the fuel pressure is within 69 kPa (10 psi) of the fuel pressure reading shown in ET. Proceed to Test Step 5. Result: The gauge value of the fuel pressure is not within 69 kPa (10 psi) of the fuel pressure reading shown in ET. Repair: Replace the pressure sensor. Verify that the problem has been resolved. If the problem is not resolved, proceed to Test Step 5.

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Table 5
Engine RPM	Fuel pressure from Cat ET	Fuel pressure from the mechanical gauge
800
1800

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Table 6
Troubleshooting Test Steps	Values	Results
5. Replace the Fuel Filters A. Replace the primary filter, the secondary filter, and the tertiary fuel filters. The fuel system will need to be primed after the filters are replaced. B. Reset all active codes by cycling the keyswitch to the Off position for 2 minutes.	Fuel Filters	Result: The problem has been resolved. Return the engine to service. Result: The problem has not been resolved. Proceed to Test Step 6.
6. Check for Air in the Fuel System A. Check for air in the fuel. Refer to Systems Operation/Testing and Adjusting, "Air in Fuel - Test" for the proper procedure	Air in the System	Result: Air is in the system. Repair: Refer to Systems Operation/Testing and Adjusting, "Air in Fuel - Test" for the proper repairs. Result: Air is not in the system. Proceed to Test Step 7.

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Illustration 2	g06140097
(11) Anti-drain check valve (12) Fuel return pressure regulator

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Table 7
Troubleshooting Test Steps	Values	Results
7. Replace the Fuel Return Pressure Regulator A. Replace the fuel return pressure regulator. B. Inspect the anti-drain check valve for proper operation.	Pressure Regulator	Result: The problem has been resolved Return the engine to service. STOP Result: The problem has not been resolved. Proceed to Test Step 8.
8. Replace the Transfer Pump A. Replace the transfer pump. For information about testing the transfer pump, Refer to Testing and Adjusting, "Fuel System Pressure - Test".	Transfer Pump	Result: The transfer pump was replaced. Reset all active codes and clear all logged codes by using Cat ET. Verify that the problem has been resolved. STOP