ELEMENT 8B5935 - Caterpillar

Use this procedure for a problem with excessive fuel consumption.Probable Causes
Look for excessive idle or high load
Logged diagnostic codes or active diagnostic codes
Fuel quality
Unstable fuel supply
Calibration procedure of the engine speed/timing
Unstable injection system
Restriction in the air inlet and exhaust
Check for damaged accessory equipmentRecommended Actions
Table 1
Troubleshooting Test Steps Values Results
1. Excessive Idle or High Load
A. Use Cat® Electronic Technician (ET) to check the Current Totals for excessive idle time and/or for a high load factor. These factors would be indicative of poor operating habits.
Idle time or load
Result: The idle times or load was excessive.
Reduce idle times or load.
Result: The idle times or load was not excessive.
Proceed to Test Step 2.
2. Check for Codes
A. Check for logged diagnostic codes or active diagnostic codes. If a diagnostic code is logged or active refer to Troubleshooting, "Diagnostic Trouble Codes" for more information.
Codes
Result: There are logged or active diagnostic codes.
Repair: Troubleshoot any logged or active diagnostic codes before continuing with this procedure. Refer to Troubleshooting, "Diagnostic Trouble Codes" for more information.
Result: There are no logged or active diagnostic codes.
Proceed to Test Step 3.
3. Fuel Quality
A. The grade of the fuel affects the rate of fuel consumption. Refer to the engines Operation and Maintenance Manual for additional information.
Note: Cold weather adversely affects the characteristics of the fuel. Refer to the Operation and Maintenance Manual for information on improving the characteristics of the fuel during cold-weather operation.
Fuel quality
Result: The fuel quality meets specifications.
Proceed to Test Step 4.
Result The fuel quality does not meet specifications.
Repair: Replace the fuel with fuel that meets specifications.
4. Calibration Procedure of the Engine Speed/Timing
A. Perform a speed/timing sensor calibration. Refer to the calibration procedure Troubleshooting, "Timing - Calibrate".
Timing Calibration
Result The speed timing calibration was performed.
Proceed to Test Step 5.
5. Unstable Injection Actuation System
A. Check for correct installation of the J1/P1 and J2/P2 Electronic Control Module (ECM) connectors and the injector connectors. Refer to Troubleshooting, "Electrical Connectors - Inspect".
B. Perform the "Injector Solenoid Test" on Cat ET in order to determine if all of the injector solenoids are being energized by the ECM.
C. Perform the "Cylinder Cutout Test" on Cat ET in order to identify any injectors that might be misfiring. Refer to Troubleshooting, "Injector Solenoid - Test".
Injection actuation
Result The tests completed successfully.
Proceed to Test Step 6.
Result The tests did not complete successfully.
Repair: Make the necessary repairs. Verify that the repair resolved the problem.
6. Restriction in the Air Inlet and Exhaust
A. Inspect the air filter for a restriction.
B. Check the air inlet and exhaust system for restrictions and/or for leaks.
Restrictions
Result There are restrictions in the air inlet or exhaust system.
Repair: Remove or repair the restrictions.
Result There are no restrictions in the air inlet or exhaust system.
Proceed to Test Step 7.
7. Check for Damaged Accessory Equipment
A. Check all accessory equipment for problems that may create excessive load on the engine.
Accessory equipment
Result There is damaged accessory equipment.
Repair: Remove or repair the accessory equipment.
If this procedure did not resolve your issue, contact your local Cat Technical Communicator (TC). For further assistance, your TC can confer