Fuel Pump Replacement: When And Why You Should Do It

Fuel pumps are an essential component of a car's fuel system, transferring fuel from the tank to the engine. While they are built to last, fuel pumps are not indestructible and may eventually need to be replaced. This raises the question: should you replace your fuel pump proactively or wait until it shows signs of failure? On the one hand, preventive maintenance can provide peace of mind and potentially avoid the inconvenience of a breakdown during a long trip. On the other hand, fuel pump replacement can be a challenging and time-consuming task, and doing it proactively may not always be necessary. This decision involves weighing the benefits of proactive maintenance against the time and cost involved in replacing the fuel pump.

Signs of a faulty fuel pump

A fuel pump is a small electric motor that transfers fuel from the fuel tank to the engine. It is an essential part of a car's combustion process and, therefore, its performance. A faulty fuel pump can wreak havoc on your car's performance and even leave you stranded on the side of the road. Here are some signs that indicate a faulty fuel pump:

• Difficulty in starting the car: If your vehicle is struggling to start or isn't starting at all, it could be due to a faulty fuel pump that is unable to deliver fuel to the engine.
• Engine sputtering or stalling: If your engine is sputtering or stalling during your drive, especially during acceleration or when under stress (e.g., towing a heavy load or driving uphill), it could be because the faulty fuel pump is causing low pressure and an inconsistent flow of fuel to the engine.
• Engine surges: If your engine is surging, repeatedly picking up and dropping speed without any input from you, it could be because the fuel pump is delivering too much fuel to the engine.
• Whining noise from the fuel tank: If you hear a loud, high-pitched whining or whirring noise coming from the fuel tank, it could be a sign that the fuel pump is damaged. A normal, functional fuel pump makes a low, barely noticeable hum.
• Poor fuel efficiency: If you notice that your vehicle's fuel efficiency has decreased significantly, it could be because a faulty fuel pump is letting excess fuel into the engine, causing more of it to go to waste.
• Engine misfire: If the fuel pump cannot supply enough fuel to the engine, causing one or more cylinders to fire too late or not at all, it can result in an engine misfire, leading to a rough idle or difficulty starting the car.
• Stalling at high temperatures: A faulty fuel pump may cause your vehicle to stall when it gets hot because it struggles to supply enough fuel to the engine under high-temperature conditions.
• Power loss: A faulty fuel pump may not be able to keep up with the demands of the engine, especially at higher speeds, leading to power loss during acceleration.
• High engine temperature: An increase in the engine's temperature, as shown on the temperature gauge, could be one of the first signs of a failing fuel pump.

If you notice any of these signs, it is recommended that you consult a professional mechanic immediately to diagnose and address the issue.

When to replace it

Fuel pumps are durable but not indestructible, and they will need to be replaced at some point. Typically, you shouldn't need to replace a fuel pump before 100,000 miles, but there are exceptions. Some pumps last beyond 200,000 miles.

There are some common symptoms that indicate it's time to replace your fuel pump:

• Difficulty starting the car
• Sudden loss of power while driving
• Rough run or stalling
• Strange, high-pitched whining noises coming from the fuel tank area

If you notice any of these issues, it's important to have your vehicle checked by a professional mechanic as soon as possible. A malfunctioning fuel pump can lead to bigger and more expensive problems if left unattended.

Additionally, consider replacing your fuel pump as a preventive measure if you own a vintage carbureted car with an overhead cam, such as a 2002. The fuel pump in these cars is easily accessible and simple to replace, making it a straightforward task to swap out the pump before a long trip or as a routine maintenance item.

Cost of replacement

The cost of replacing a fuel pump varies depending on the vehicle, its age, and the region. The average cost of a fuel pump replacement is between $220 and $1,321, with some estimates giving a range of $1,000 to $1,300. The parts cost between $95 and $1,110, while labour costs range from $124 to $700 per hour, with an average of $90 per hour. The total labour cost for the job is estimated to be between $168 and $600.

The cost of the replacement also depends on the make and model of the vehicle. For instance, newer models from automakers like BMW, Honda, Chevrolet, and Toyota have an average cost for fuel pump replacement between $611 and $894. The type of engine will also affect the price: a diesel engine with a mechanical fuel pump will cost up to $1,500, whereas a gasoline engine with an electric fuel pump will be cheaper.

It is important to note that the above estimates may not include taxes and fees, and related repairs may also be needed, which can increase the overall cost of the replacement.

How to replace it

How to Replace a Fuel Pump

Step 1: Identify the Problem

Firstly, you need to identify whether your fuel pump is faulty. If your engine is struggling to start, you experience a sudden loss of power while driving, or you hear strange, high-pitched whining noises coming from the fuel tank area, your fuel pump may be malfunctioning.

Step 2: Prepare

Before starting, gather the necessary tools and equipment, including a new fuel pump, fuel filter, and any other vehicle-specific components. It is also recommended to reduce the amount of fuel in the tank to prevent spillages and make the tank lighter and easier to handle. Ensure you have a safe and accessible workspace, and take safety precautions such as disconnecting the battery.

Step 3: Relieve the Fuel System Pressure

There are two ways to do this. With the engine on, pull the fuel pump relay, causing the engine to stall. Alternatively, with the engine off, press the Schrader valve on the pressure line momentarily, capturing the small amount of fuel that sprays out.

Step 4: Locate and Remove the Fuel Tank

The fuel tank is usually located directly in the fuel tank, but this varies by vehicle. You may need to remove the fuel tank from the vehicle, using a jack to support and lower it. Alternatively, there may be an access port under the rear seat or in the trunk.

Step 5: Remove the Old Fuel Pump

Note the fuel line connections and wiring before removing the old pump. Remove all connections, turn the large lock nut to free the old pump, and pull it out.

Step 6: Install the New Fuel Pump

Compare the new fuel pump with the old one to ensure you have the correct part. Install the new pump, reassemble the fuel system, and test the pump to ensure it is functioning correctly.

Additional Tips:

• Work in a well-ventilated area to minimise the risk of fire and inhaling harmful fumes.
• Wear safety gear, including glasses, gloves, and appropriate clothing, to protect yourself from fuel spills.
• Clean around the fuel pump before removing it to prevent dirt and debris from falling into the fuel tank.
• Consider replacing related components, such as the fuel filter, fuel pump strainer, and fuel tank O-ring or gasket.

Preventative maintenance

Fuel pumps are not a regular maintenance item and are generally replaced on an as-needed basis. However, there are some preventative maintenance measures you can take to increase the reliability of your fuel pump and decrease the cost of ownership. Here are some tips:

Use High-Quality Fuel

Use a quality TIER 1 fuel from a reputable brand. This includes brands like BP, Sunoco, Shell, Marathon, and Chevron.

Maintain Fuel Levels

Remember that the fuel pump is an electrical motor that heats up. To prevent overheating, try to never run the fuel level down below half a tank. This ensures that the pump stays immersed in fuel and maintains a cool temperature.

Avoid Fueling Up During Fuel Deliveries

When you're getting fuel, avoid doing so if the station is getting a fuel delivery at the same time. The process of delivering fuel stirs up dirt and deposits, and the gasoline pump filters may not catch all of them.

Regularly Change the Fuel Filter

If your vehicle has a fuel filter that is not in the tank, change it yearly, regardless of mileage. A clogged fuel filter can cause the fuel pump to strain and eventually fail.

Add an Anti-Ethanol Agent

If you don't burn a tank of fuel every week or two, be sure to add an anti-ethanol agent to prevent the fuel from gelling. Fuel separation is a common cause of fuel pump and injector failure.

Additionally, while not directly related to the fuel pump, it is important to perform regular maintenance on your vehicle, such as oil changes and filter replacements, to ensure the overall health of your car.

Frequently asked questions