ROD 7J7526 - Caterpillar

Note: If the symptom is intermittent and the symptom cannot be repeated, refer to Troubleshooting, "Intermittent Low Power or Power Cutouts". If the symptom is consistent and the symptom can be repeated, continue with this procedure.Probable Causes
Cold Mode
Throttle position sensor
Direct Fuel Control
Injection actuation pressure
Electrical connectors
Unit injectors
Fuel supply
Air inlet and exhaust systemRecommended Actions
Note: If the symptom only occurs under certain operating conditions (high idle, full load, engine operating temperature, etc), test the engine under those conditions. Troubleshooting the symptom under other conditions can give misleading results.Cold Mode
Use the Caterpillar Electronic Technician (ET) to verify that the engine has exited Cold Mode. Cold Mode operation may cause the engine to run rough and engine power may be limited.Throttle Position Sensor
Monitor the status of the throttle position on ET. Verify that the throttle position sensor is operating correctly. Refer to Troubleshooting, "Throttle Position Sensor Circuit - Test" for the proper troubleshooting procedure.Direct Fuel Control
Monitor the status of the throttle position on ET. Verify that the direct fuel control is operating correctly. Refer to Troubleshooting, "Throttle Position Sensor Circuit - Test" for the proper troubleshooting procedure.Injection Actuation Pressure
Check the engine oil level. Engine oil supplies the injection actuation pressure circuit. The engine oil must be kept at the proper level for fuel injection.Note: If the oil has been drained from the unit injector hydraulic pump, the pump must be primed. Refer to Disassembly and Assembly, "Unit Injector Hydraulic Pump - Install" for the correct procedure.
If service has recently been performed on the engine, air may be present in the injection actuation pressure circuit. Allow the engine to fully warm up and operate the engine under load in order to purge the air from the injection actuation pressure circuit.
Use ET to check for diagnostic codes. If there is an Active Diagnostic Code for Injection Actuation Pressure, refer to the appropriate topic in Troubleshooting with a Diagnostic Code in this manual.
Compare the actual actuation pressure and the desired actuation pressure on the ET Status screen. If these readings agree within 2000 kPa (290 psi) during the symptom, the problem is not in the injection actuation pressure circuit.
Check the seals on the injection actuation pressure control valve. If the seals are faulty, replace the seals and repeat Step 4.
Check the wiring harness to the injection actuation pressure control valve for opens and/or shorts.
Measure the coil resistance on the injection actuation pressure control valve. If the coil resistance is not within 10 5 Ohms, replace the injection actuation pressure control valve.
Escaping fluid under pressure, even a pinhole size leak, can penetrate body tissue, causing serious injury, and possible death. If fluid is injected into your skin, it must be treated immediately by a doctor familiar with this type of injury.Always use a board or cardboard when checking for a leak.
Use ET to perform the Injection Actuation Pressure Override Test. If the injection actuation pressure is low, the high pressure oil supply circuit may have a leak.
Unplug the injection actuation pressure control valve and the unit