As an experienced mechanic, I’ve seen firsthand how crucial a properly functioning fuel pump is to a vehicle’s overall performance. The fuel pump is responsible for delivering the right amount of fuel from the gas tank to the engine. When it’s working correctly, your car runs smoothly and efficiently. However, a bad fuel pump can create numerous problems and even prevent your car from starting altogether.

In this blog post, we’ll discuss the symptoms of a bad fuel pump, so you know what to look out for. We’ll also explore some temporary solutions that can help you start your car in a pinch, but remember that these are only short-term fixes. It’s essential to address a bad fuel pump issue quickly to prevent further damage to your vehicle and ensure your safety on the road.

Stay tuned for tips and tricks on how to start a car with a bad fuel pump, as well as permanent solutions to get your vehicle back to peak performance.

What Is A Fuel Pump And How Does It Work?

A fuel pump is an essential component in any internal combustion engine-powered vehicle. Its primary function is to supply fuel from the gas tank to the engine. This process ensures that the engine receives the necessary fuel for combustion, which in turn powers the vehicle.

Types of Fuel Pumps

There are two main types of fuel pumps: mechanical and electric.

• Mechanical fuel pumps are typically found in older vehicles with carbureted engines. They are driven by the engine’s camshaft and operate using a diaphragm mechanism to pump fuel from the tank to the carburetor.
• Electric fuel pumps, on the other hand, are commonly used in modern vehicles with fuel-injected engines. They are typically located inside or near the fuel tank and use an electric motor to pump fuel through the fuel lines and into the engine’s fuel injection system.

How a Fuel Pump Works

Regardless of the type, a fuel pump works by creating pressure within the fuel system. This pressure pushes the fuel from the tank, through the fuel lines, and into the engine. The fuel pump maintains a consistent flow, ensuring that the engine receives the optimal amount of fuel for efficient combustion.

In the case of an electric fuel pump, the pump is activated when the ignition is turned on. A relay sends power to the pump, and the electric motor begins to spin, creating suction to draw fuel from the tank. The fuel then passes through a strainer, removing any debris or contaminants before it reaches the engine. Finally, the fuel is sent through the fuel lines and into the fuel injection system, where it is mixed with air and burned in the engine’s cylinder

Causes of a Bad Fuel Pump

As an experienced mechanic, I’ve seen various reasons that can lead to fuel pump failure. Let’s take a look at some of the most common causes so you can better understand why your fuel pump might be acting up.

a. Wear and Tear: Like any other mechanical component, fuel pumps are subject to wear and tear over time. As your vehicle ages, the internal parts of the fuel pump can degrade, leading to a loss of performance or complete failure.

b. Contaminated Fuel: Debris and contaminants in the fuel tank can cause damage to the fuel pump. These impurities may be introduced during refueling or as a result of rust and corrosion inside the tank. When contaminants enter the fuel pump, they can clog the strainer or impede the pump’s moving parts, eventually causing failure.

c. Running on Empty: Frequently driving your vehicle with a near-empty gas tank can shorten the life of your fuel pump. The fuel in the tank helps to keep the pump cool and lubricated. When the fuel level is too low, the pump can overheat, leading to premature wear and failure.

d. Electrical Issues: Faulty wiring, damaged connectors, or a malfunctioning relay can interrupt power supply to the electric fuel pump, causing it to stop working. It’s important to inspect and maintain your vehicle’s electrical system to prevent these issues from affecting the fuel pump.

Diagnosing a Bad Fuel Pump

If you suspect your fuel pump is failing, there are a few telltale signs to watch out for:

• Poor engine performance, such as hesitation, stalling, or misfiring, especially under load or at high speeds
• Difficulty starting the vehicle, or the engine not starting at all
• Decreased fuel efficiency
• A noticeable whining or buzzing noise coming from the fuel tank area

As a mechanic, I would typically use a fuel pressure gauge to test the fuel pump’s output pressure. If the pressure is lower than the manufacturer’s specifications, it’s likely the fuel pump is failing or has already failed. Additionally, inspecting the fuel filter and checking for any electrical issues can help pinpoint the root cause of the problem.

How To Start a Car With a Bad Fuel Pump (Temporary Solutions)

Temporary solutions to start a car with a bad fuel pump include cycling the ignition, using a fuel pressure booster, and applying external pressure to the fuel tank. These methods can help get your vehicle running, but should only be used as a last resort

If you find yourself in a situation where your car won’t start due to a bad fuel pump, these are “quick fixes” that can help you get back on the road. Keep in mind, these methods are not recommended for long-term use.

Always consult a professional mechanic to address the issue as soon as possible.

Cycling the Ignition

This technique can help build enough pressure in the fuel system to start your car.

1. Insert the key into the ignition and turn it to the ‘ON’ position (without cranking the engine). This will activate the fuel pump.
2. Wait for a few seconds, allowing the pump to build up pressure in the fuel lines.
3. Turn the key back to the ‘OFF’ position.
4. Repeat steps 1-3 a few times to build up sufficient fuel pressure.
5. Attempt to start the engine by turning the key to the ‘START’ position.

Using a Fuel Pressure Booster

A fuel pressure booster can help increase the fuel pressure temporarily, which may allow your engine to start.

1. Locate the fuel pressure test port on your vehicle’s fuel rail.
2. Connect the fuel pressure booster to the test port, following the manufacturer’s instructions.
3. Turn the booster on and wait for a few seconds to allow the fuel pressure to build up.
4. Try starting the engine while the booster is running.
5. Once the engine starts, disconnect the booster and close the fuel pressure test port.

Note: It’s important to use a fuel pressure booster that is compatible with your vehicle’s fuel system. Consult your owner’s manual or a professional mechanic for guidance.

Applying External Pressure to the Fuel Tank

This method involves manually applying pressure to the fuel tank to force fuel into the engine. Please exercise caution, as this method can be potentially dangerous.

1. Locate your vehicle’s fuel tank, typically found under the rear of the car.
2. Use a rubber mallet or the palm of your hand to gently tap on the bottom of the fuel tank. This may help dislodge any debris that could be blocking the fuel pump’s strainer.
3. While continuing to apply pressure, have someone attempt to start the engine.

Remember, these temporary solutions are not meant to address the underlying issue with your fuel pump. Always seek professional help to properly diagnose and repair the problem to ensure the safety and reliability of your vehicle.

How To Start a Car With a Bad Fuel Pump (Permanent Solutions)