G3600 A4 Engines Fuel Energy Content Problem Caterpillar

Fuel Energy Content Problem
1.1. Probable Causes
2.1. Recommended Actions

Use this procedure in order to troubleshoot a fuel energy content problem. Also, use this procedure if one of the following event codes is active or logged.

Table 1
J1939 Code and Description  Comments 
Fuel Energy Content : High - most severe (3) 
The code is logged. 
Fuel Energy Content : High - least severe (1) 
The code is logged. 
Fuel Energy Content : Low - least severe (1) 
The code is logged. 

Probable Causes

  • Codes

  • Sensor

  • Low Heating Value (LHV)

  • Pretreatment equipment

  • Cylinder misfire

Recommended Actions

Table 2
Troubleshooting Test Steps  Values  Results 

1. Check for Codes

A. Connect Cat® Electronic Technician (ET) to the service tool connector.

B. Look for active codes that are associated with the system for the event code.


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. Verify that the NOx Sensor is Calibrated


Result: The NOx sensor is OK.

Proceed to Test Step 3.

Result: The NOx sensor is NOT OK.


If the problem is not resolved, proceed to Test Step 3.

3. Determine the Low Heating Value (LHV)

A. Obtain a fuel analysis.

Note: If the quality of the gas is inconsistent, obtain several analyses over a period of time.

B. Enter the data into AVSpare Software, LERW4485, "Gas Engine Rating Pro (GERP)".

C. Verify that the exhaust emissions are correct.


Result: The LHV is OK.

Proceed to Test Step 4.

Result: The LHV is NOT OK.

Repair: Use Cat ET to program the results for the "Fuel Quality" and "Gas Specific Gravity" parameters. Refer to Systems Operation, "Electronic Control System Parameters" for additional information.

Program the "Fuel Quality" parameter to the average value of the LHV. Adjust the engine operation according to Testing and Adjusting, "BTU and Precombustion Chamber Adjustments".

If the problem is not resolved, proceed to Test Step 4.

4. Inspect the Gas Pretreatment Equipment

A. Check for condensation.

Note: Any condensation in the gas will change the fuel energy content.

B. Make sure that the filter and the dryer for the gas operate properly.

Pretreatment Equipment

Result: The gas pretreatment equipment is operating properly.

Proceed to Test Step 5.

Result: The gas pretreatment equipment is not operating properly.

Repair: Repair or replace the gas pretreatment equipment. For information on gas pretreatment equipment, refer to the Original Equipment Manufacturers (OEM) service information.

If the problem is not resolved, proceed to Test Step 5.

5. Check for a Cylinder Misfire


Result: There is a cylinder misfire.

Repair: Troubleshoot the cause of the misfire. Refer to Troubleshooting, "Engine Misfires, Runs Rough, or Is Unstable" additional information.

Verify that the repair eliminated the problem.

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).