GASKET-HEAT EXCHANGER 3H5939 - Caterpillar

Probable Causes
Fuel supply
Electrical connectors or power supply
Engine speed/timing sensor
Ignition system
Excessive loadRecommended Repairs
Fuel Supply
Make sure that fuel is supplied at a sufficient pressure that is stable. Make sure that the size of the fuel line is sufficient. Inspect the fuel system for leaks.The following conditions can cause the engine to malfunction:
Low fuel pressure
High fuel pressure
Poor fuel qualityMake sure that the fuel pressure is correct. When possible, interview the operator in order to determine if fuel quality is in question. Try to determine if the source of the fuel was changed.Inspect the fuel system components: fuel filter, gas pressure regulator, gas shutoff valve, fuel metering valve and actuator for the throttle. Verify that the system's components are operating correctly.Replace the fuel filter, if necessary.Electrical Connectors or Power Supply
Inspect the power supply connections and the ground. Check the wiring harnesses and the connectors from the power supply to the terminal box for the master Electronic Control Module. Inspect the connectors in each terminal box. Refer to Troubleshooting, "Inspecting Electrical Connectors".
Use the Caterpillar Electronic Technician (ET) to check for the 168-02 diagnostic code for "System Voltage Intermittent". If this diagnostic code is logged, proceed to Troubleshooting, "Electrical Power Supply".Engine Speed/Timing Sensor
Make sure that the speed/timing sensor is installed correctly. See Troubleshooting, "Engine Speed/Timing Sensor".Make sure that the timing wheel is correctly installed.Ignition System
Inspect the ignition transformers for loose connections, moisture, short circuits, and open circuits. Inspect the primary wiring and the secondary electrical connections.Make sure that the correct transformers and spark plugs are installed. Inspect the extenders for signs of pin holes and of arcing.Maintain the spark plug according to the engine's Operation and Maintenance Manual.Excessive Load
Make sure that the load is not excessive. Reduce the load. If necessary, disengage the driven equipment and test the engine.