While a failing fuel pump often necessitates replacement, there are troubleshooting steps and temporary fixes you can try to get back on the road. These are NOT long-term solutions; plan to replace the fuel pump ASAP if these provide temporary relief. The goal is to diagnose the problem and potentially move your vehicle to safety or a mechanic.

Diagnosing the Problem: Is it Really the Fuel Pump?

Before diving in, confirm the fuel pump is the actual problem. Misdiagnosis is common. Check these before assuming pump failure:

  • Check the Fuel Level: Running out of gas happens! Make sure you have fuel.
  • Listen for Fuel Pump Priming: Turn the key to the “on” position (before starting); you should hear a faint whirring from the fuel tank. No sound indicates a fuel pump issue.
  • Check the Fuel Pump Relay and Fuse: A blown fuse or faulty relay is a common culprit. Consult your owner’s manual to locate them.
    • Relay: Swap the fuel pump relay with an identical one (like the horn) to see if it resolves. If so, replace the faulty relay.
    • Fuse: Check the fuse. If blown, replace it. If it blows again, you have a short circuit.
  • Check for Fuel Pressure: Use a fuel pressure gauge to check fuel pressure at the fuel rail. Compare the reading to your vehicle’s specifications. Low or no fuel pressure points to a fuel pump issue or a clogged fuel filter.
  • Check the Fuel Filter: A clogged fuel filter restricts fuel flow and can mimic fuel pump failure. Replace it regularly as part of maintenance.

If you’ve ruled out easier fixes, consider these temporary methods.

Potential Temporary Fixes (Proceed with Caution!)

Warning: Working on fuel systems involves flammable materials. Work in a well-ventilated area, disconnect the negative battery terminal, and avoid sparks or open flames. If uncomfortable, seek professional help.

1. The “Fuel Tank Tap” (Desperate Measures Only!)

This is a last-ditch effort and unlikely to work, but some try it when stranded. The idea is that the fuel pump motor is stuck.

  • Locate the Fuel Tank: Determine your fuel tank’s location.
  • Gently Tap the Tank: Using a rubber mallet, gently tap the bottom of the fuel tank where the fuel pump is. Don’t hit it hard!
  • Try to Start the Engine: After tapping, try to start the engine. If the pump was stuck, vibration might dislodge the problem.
  • Repeat if Necessary: You may need to repeat the tapping process.

Why this is risky: This is unreliable and can damage the fuel tank. It rarely works.

2. Check Electrical Connections to the Fuel Pump

Sometimes, a loose or corroded electrical connection can prevent the fuel pump from receiving power.

  • Locate the Fuel Pump Wiring Harness: Find the wiring harness that connects to the fuel pump (usually accessible from under the vehicle near the fuel tank or through an access panel inside the vehicle).
  • Inspect the Connections: Check for loose connections, corrosion, or damaged wires.
  • Clean the Connections: Use electrical contact cleaner to clean any corroded connections.
  • Secure the Connections: Ensure all connections are tight.
  • Test: Try starting the engine.

3. Fuel Pump Reset (If Applicable):

Some newer vehicles have a fuel pump reset switch/procedure. Consult your owner’s manual. A fuel pump inertia switch cuts off fuel in an accident and may need resetting.

4. Fuel System Cleaner

While unlikely to solve a major fuel pump issue, a high-quality fuel system cleaner can sometimes help dislodge minor deposits. Add it to your fuel tank per the instructions. This is more preventative but might offer a slight improvement.

Important Considerations:

  • Safety First: Fuel is flammable. Prioritize safety when working on fuel systems.
  • Temporary Fixes are Not Permanent: If any of these methods work, it’s temporary. The underlying problem likely exists, and the fuel pump will likely fail again.
  • Replace the Fuel Pump Soon: Schedule a fuel pump replacement ASAP.
  • Consult a Professional: If you are not comfortable or unsure, consult a qualified mechanic.

Ultimately, a failing fuel pump is serious. While these temporary fixes might help, they aren’t a substitute for professional diagnosis and replacement. Good luck, and stay safe!