Fuel Lines: Replacing Them Before They Become A Problem

Fuel lines are pipes made of rubber, metal, or plastic that transport gasoline from the fuel tank to the fuel pump. Over time, these fuel lines can become old, cracked, or broken, leading to fuel leaks and potential safety hazards. Corrosion is the primary cause of metal fuel line failure, often initiated by abrasive materials removing the paint or coating on the line. When this happens, it is essential to replace the fuel lines promptly to prevent further issues. The cost of replacing fuel lines can vary depending on the extent of the repair, the condition of the fuel lines and fittings, and whether the fuel tank needs to be removed. While it is possible to replace fuel lines yourself, it is recommended to consult a certified technician or mechanic for proper diagnosis and repairs.

Fuel line corrosion

The first sign of fuel line corrosion is often the appearance of surface rust on the lines. While light surface rust can be treated with heavy grease or rust-converting paint, more advanced rust may require replacement of the affected sections. In some cases, it may be necessary to replace the entire fuel line if the corrosion is extensive.

To prevent further corrosion and protect the fuel system, it is recommended to use fuel additives that form a protective film on metal surfaces, inhibiting the corrosive action of water. These additives are available for both diesel and petrol engines and can save significant repair costs in the long run.

When dealing with fuel line corrosion, it is essential to take safety precautions. Always work in a well-ventilated area to avoid inhaling fuel fumes, and have a fire extinguisher nearby. Ensure that the negative terminal of the car battery is disconnected to prevent any chance of electric sparks during the repair process.

If you are uncomfortable performing the replacement yourself, it is best to consult a certified technician or mechanic for proper diagnosis and repair. They will have the necessary tools and expertise to safely replace the fuel lines and ensure the vehicle's fuel system is functioning correctly.

Fuel leaks

Strong scent of gasoline

The distinct smell of gasoline in or around your vehicle is a telltale sign of a fuel leak. If the fuel tank and other components of the fuel system appear to be in good condition, then the fuel lines are likely the source of the leak. It is important to address this issue promptly, as inhaling gasoline fumes can pose health risks, including respiratory problems.

Visible fuel leaks

A leaking fuel line can result in fuel being sprayed out while driving, leaving puddles of fuel on the road. Keep in mind that smaller leaks can be harder to detect as the fuel evaporates quickly. Look out for droplets or small puddles of fuel under your vehicle. To aid in identifying gasoline puddles, consider adding a fuel-safe dye to your fuel tank.

Audible hissing sound

A hissing sound, similar to air escaping from a tire, may be heard when a fuel line is leaking. This sound is typically noticeable when the engine is idling or has been turned off.

Diminished engine performance

The fuel line plays a critical role in delivering the correct air-fuel mixture to the engine. A damaged fuel line can disrupt this balance, leading to an excess of air and insufficient fuel in the combustion chamber. This can cause issues such as misfires, unexpected power loss, and rough idling. In severe cases, the engine may overheat and sustain damage.

Illuminated check engine light

A leaking fuel line can trigger the check engine light due to the detection of an imbalance in the air-fuel ratio by sensors in the exhaust system. If the check engine light illuminates along with other signs such as a gasoline odour or hissing noise, it is likely due to a leaking fuel line.

If you suspect a fuel leak, prioritize your safety. Move away from any puddles of fuel, avoid any flames or sparks, and turn off the engine to prevent further leakage. Contact a certified technician or mechanic to properly diagnose and repair the issue.

Fuel line repair costs

In some cases, you may be able to repair only the damaged portion of the fuel line, which can be a more cost-effective option. This approach was suggested to the owner of a 1999 Olds Cutlass with three rusted and leaking fuel lines. The mechanic quoted approximately $3,000 to replace all the fuel lines or $1,500 to replace the rusted sections, leading the owner to question the fairness of the price.

The cost of fuel line repairs also depends on whether you choose to do it yourself or take it to a professional mechanic. Doing it yourself will require purchasing the necessary parts, which can cost upwards of $50, and renting or buying the required tools. You will also need the right skills and knowledge to perform the repair safely and effectively.

On the other hand, taking your vehicle to a mechanic can be more convenient and ensure a professional job, but it will typically be more expensive due to labour costs. Getting estimates from multiple shops can help you find the best price, but keep in mind that they might need to see your vehicle firsthand to provide an accurate quote.

It's worth noting that fuel lines are usually covered under factory bumper-to-bumper warranties, and your vehicle may also qualify for a special CARB emissions warranty in certain states, which can help offset the cost of repairs. However, warranties typically do not cover physical damage, which is the leading cause of fuel line failure.

DIY fuel line replacement

When to Replace Fuel Lines

Fuel lines are the rubber, metal, or plastic pipes through which gasoline passes from the fuel tank to the fuel pump, and then into the engine's combustion chamber. If your fuel line is old, cracked, or broken, it needs immediate maintenance or replacement. Signs that your fuel line is damaged include the smell of gasoline and puddles of fuel under your car.

Step-by-Step Guide to DIY Fuel Line Replacement

Disclaimer: This is a general guide and may not apply to all vehicles. Always consult a certified technician or your vehicle's handbook manual for advice specific to your car.

Emptying the Fuel Line

First, locate your car's fuse box, usually found under the passenger-side glove box. Remove the fuse for the fuel pump, start the car, and let it run until the engine turns off. This will burn up any remaining fuel in the line.

Finding the Fuel Line

Open up the engine space and find the fuel line. Follow it to locate where it connects to the carburetor or fuel injection unit. Jack up the car so you can crawl under it and see the other end of the line.

Removing the Fuel Line

The fuel line is locked in place by holders screwed or bolted onto the car. Remove the connection to the engine compartment first. You may need to use a special solvent to get the fittings to come off easily. Remove each section of the fuel line one by one. This part can be tricky, so it's helpful to have an assistant shine a flashlight on the area you're working in.

Placing the New Fuel Line

Insert one end of the new fuel line into the engine compartment, fixing it in place where the old fuel line was. Ensure any hardware will face you when the line is in place so that the clamps can be easily tightened. Check the fit of the new line, ensuring it is not too short or too long. If there are kinks or bends in the line, the gasoline may not flow properly. Once you're happy with the fit, tighten the clamps with a screwdriver.

Final Steps

Before starting the car, reconnect the negative terminal on the car battery and reinsert the fuel pump fuse. When you start the engine, it may take a few seconds for the fuel to begin flowing. Check your work for any fuel leaks. If you find a leak, turn off the car and repair it immediately, taking the necessary safety precautions.

Tools and Materials

• Screwdrivers (Phillips and flathead)
• Knife
• Floor jack
• Jack stands
• Vice grips
• Replacement fuel line
• Fuel hose clamps
• Rags
• Eye protection
• Old clothes
• Fire extinguisher

Fuel line maintenance

Fuel lines are pipes made of rubber, metal, or plastic that transport gasoline from the fuel tank to the fuel pump, which then squirts the fuel into the engine's combustion chamber. As such, they are integral to the functioning of a car and require regular maintenance.

When to Replace Fuel Lines

The main reason metal fuel lines fail is corrosion, which can be caused by abrasive materials removing the paint or coating on the line. This can occur at a mounting bracket or from debris kicked up from the tire. If the fuel lines are old, cracked, or broken, they need immediate maintenance or replacement. Signs that your fuel lines need replacing include a constant smell of gasoline and fuel leaking onto the pavement.

DIY vs. Professional Replacement

Replacing fuel lines can be done by either a professional mechanic or by yourself. While a professional will be able to safely and efficiently replace the fuel lines, it will cost more due to labor and recycling or disposal fees. On the other hand, doing it yourself will save you money, but it will require time, patience, and the right tools and instructions.

Steps for DIY Fuel Line Replacement

First, purchase replacement fuel hoses and fuel hose clamps online or at a vehicle maintenance store. Make sure to buy the correct size hoses for your vehicle's make, model, and year. Then, gather the necessary tools, including a screwdriver, pliers, a knife, a floor jack, jack stands, vice grips, and the replacement parts. Work in a well-ventilated area to avoid gas fumes, keep a fire extinguisher on hand, and wear protective clothing and eye gear.

Next, safely lift your vehicle using a floor jack and secure it with jack stands. Locate the fuel lines and fuel filter, then relieve the pressure in your fuel system by locating and removing the fuse or relay for the fuel pump. Disconnect the negative terminal on your car's battery to avoid any chance of an electric spark.

Now, you can remove the old fuel hoses by loosening the hose clamps and sliding them back and forth. Place a catch pan or towel underneath to catch any leaking gasoline. Once the clamps are loose, remove the fuel hose and locate and remove the other end.

Finally, install the new fuel line by sliding the open ends into place and checking the fit. Ensure the hose is not too long or too short, and there are no kinks or bends that could impede the gasoline flow. Tighten the clamps with a screwdriver, then connect the negative terminal on your car's battery and pressurize the fuel system by returning the fuel pump fuse. Start the engine and inspect your work for any fuel leaks.

Cost of Fuel Line Replacement

The cost of fuel line replacement can vary depending on whether you do it yourself or take it to a shop. Fuel line sets typically cost less than $200, and doing it yourself can save you hundreds of dollars in labor costs. At a repair shop, the cost can range from $300 to $500 for a basic fuel line repair, but prices can increase to $1,000 or more if the fuel lines are in bad condition or if the gas tank needs to be removed.

Frequently asked questions