Fuel Delivery System:
* Empty Fuel Tank: The most obvious! Check your fuel gauge.
* Fuel Pump: The pump may be failing, clogged, or have a faulty relay. This is a very common issue with older vehicles. Symptoms include a lack of fuel pressure or weak pressure.
* Fuel Filter: A clogged fuel filter restricts fuel flow. This is a relatively cheap and easy component to replace.
* Fuel Lines: Cracks, kinks, or leaks in the fuel lines can interrupt fuel flow. Inspect visually for damage, especially near the tank and engine. Fuel line corrosion is also possible.
* Fuel Pressure Regulator: If this is faulty, it may not maintain the correct fuel pressure.
* Clogged Fuel Injector(s): The injectors spray fuel into the cylinders. Clogged injectors prevent proper fuel delivery. This often leads to rough running or misfires *if some fuel is still getting through*.
Electrical System (related to fuel delivery):
* Fuel Pump Relay: This relay switches the power on and off to the fuel pump. A bad relay will prevent the pump from working.
* Fuel Pump Wiring: Damaged wiring can prevent power from reaching the fuel pump.
* In-Tank Fuel Pump Wiring Harness: This harness is susceptible to corrosion, causing intermittent or complete failure.
* PCM (Powertrain Control Module): The PCM controls many aspects of the fuel system. A faulty PCM can prevent the fuel pump from activating or cause other fuel delivery issues. This is a less likely culprit, but possible.
Other Possibilities:
* Fuel Tank Sender Unit: While this doesn't directly stop fuel flow, a faulty sender could give a false reading on the fuel gauge, leading you to believe you have more fuel than you do.
* Evaporative Emission System (EVAP) issues: A severely malfunctioning EVAP system *might* indirectly affect fuel delivery in some rare cases, though it's less likely to completely stop fuel flow.
* Security System: In some cases, a malfunctioning immobilizer or security system could prevent the engine from starting even if fuel is present. This often involves an issue with the key or the vehicle's computer system.
Troubleshooting Steps:
1. Check the fuel gauge: Is the tank actually empty?
2. Listen for the fuel pump: Turn the ignition key to the "on" position (don't crank the engine). You should hear a brief whirring sound from the fuel pump area (usually near the fuel tank). If you don't hear it, the pump or its relay may be the problem.
3. Check fuel pressure (requires a fuel pressure gauge): This is the most definitive way to determine if the fuel pump and system are delivering adequate pressure.
4. Visual inspection of fuel lines and filter: Look for any obvious damage or leaks.
If you are not comfortable working on your vehicle's fuel system, take it to a qualified mechanic. Working with fuel is dangerous, and mistakes can lead to fire or injury.
