1. Check the Obvious:
* Empty Gas Tank: The most basic cause! Make sure you have enough gas.
* Power to the Fuel Pump: This is the most common problem. You'll need to test this electrically. WARNING: Working with car electrical systems can be dangerous. If you are not comfortable with this, take it to a mechanic.
* Listen for the Prime: Turn the ignition key to the "ON" position (don't start the engine). You should hear a brief whirring sound from the fuel pump (located in the fuel tank). If you don't hear anything, there's likely a power issue.
* Check the Fuel Pump Relay: Locate the fuel pump relay in the underhood fuse box (consult your owner's manual for the exact location). You can swap it with another relay of the same amperage (if possible, to rule out a bad relay).
* Check the Fuel Pump Fuse: Also check the fuse for the fuel pump in the fuse box. Replace if blown.
* Voltage Test: Using a multimeter, check for voltage at the fuel pump's electrical connector. You should have battery voltage (around 12V) when the ignition is turned on. Lack of voltage here points to a wiring problem, relay issue, or a problem in the fuel pump circuit.
2. If you have power to the pump, but it still isn't working:
* Bad Fuel Pump: The most likely culprit if you have power and hear nothing. Replacing the fuel pump is typically the solution. This involves dropping the fuel tank, which can be a significant job.
* Clogged Fuel Filter: A clogged fuel filter can restrict fuel flow, preventing the pump from working effectively. It's a relatively inexpensive and easy part to replace, so it's worth checking.
* Fuel Pump Wiring Harness: Check for any broken wires or corrosion in the wiring harness leading to the fuel pump.
3. Other Less Common Issues:
* Inertia Switch: Some vehicles have an inertia switch that cuts power to the fuel pump in a collision. Check your owner's manual for its location and reset it if necessary.
* PCM (Powertrain Control Module) Problems: In rare cases, a malfunctioning PCM can prevent the fuel pump from activating. This requires a diagnostic scan tool.
Recommendations:
* Consult your owner's manual: It will contain specific information on the location of fuses, relays, and other components relevant to your 2002 Chevy Impala.
* Use a repair manual: A Haynes or Chilton repair manual for your vehicle will provide detailed instructions and diagrams for troubleshooting and repair.
* Consider a professional: If you're not comfortable working on your car's electrical system or fuel system, take it to a qualified mechanic. Replacing a fuel pump is a somewhat involved job.
Remember safety first! Work in a well-ventilated area, and disconnect the negative battery terminal before working on any electrical components. Gasoline is highly flammable, so take appropriate precautions.
