High-Probability Causes:
* Fuel Pump Failure: The fuel pump is the heart of the system. If it's not working, no fuel reaches the injectors. Listen for the pump whirring when you turn the key (some pumps are quieter than others). A low fuel pressure reading confirms this.
* Fuel Filter Clog: A clogged fuel filter restricts fuel flow, preventing sufficient fuel from reaching the injectors. This is a relatively inexpensive and easy fix.
* Low Fuel Level: Sounds obvious, but make absolutely sure the tank has enough fuel.
* Relay or Fuse Issues: The fuel pump and other fuel system components are controlled by relays and fuses. A blown fuse or faulty relay will cut power to the system. Check your vehicle's owner's manual for their locations.
* Fuel Pressure Regulator Malfunction: This regulates fuel pressure within the system. A faulty regulator could cause low or no fuel pressure.
Medium-Probability Causes:
* Clogged Fuel Injectors: Injectors can become clogged with debris, preventing them from spraying fuel. This often results in rough running or misfires before complete failure.
* Faulty Crankshaft Position Sensor (CKP): The CKP sensor tells the computer the engine's rotational position. Without this signal, the computer won't command fuel injection.
* Faulty Camshaft Position Sensor (CMP): Similar to the CKP, the CMP sensor provides information about the camshaft's position. A malfunction can disrupt fuel injection timing.
* Faulty Mass Airflow Sensor (MAF): The MAF sensor measures the amount of air entering the engine. A faulty MAF sensor can cause the computer to send incorrect fuel commands.
* Problems with the PCM (Powertrain Control Module) / ECU (Engine Control Unit): The PCM/ECU is the "brain" of the system. A malfunctioning PCM/ECU can cause a wide array of problems, including no fuel injection. This is usually the least likely but most expensive issue.
Low-Probability Causes (often related to prior issues or modifications):
* Wiring Problems: Damaged or corroded wiring can interrupt the electrical signals to the fuel pump, injectors, or other components.
* Improper Installation of Aftermarket Parts: If recent modifications were made, check all connections and installations.
Troubleshooting Steps:
1. Check the fuel level.
2. Listen for the fuel pump.
3. Check fuses and relays.
4. Measure fuel pressure (requires a fuel pressure gauge). This is a crucial step for diagnosis.
5. Inspect the fuel filter for clogs.
6. Have a professional mechanic perform a diagnostic scan. This will read codes from the PCM/ECU which can pinpoint the problem more precisely.
Important Note: Attempting to diagnose and repair fuel system issues yourself can be dangerous due to the flammability of gasoline. If you're not comfortable working on your truck's fuel system, take it to a qualified mechanic. They have the tools and expertise to diagnose the problem safely and efficiently.
