Whenever you fill up your tank at a station, the fuel filler neck is where you primarily pump the gasoline into. It is such a minor part of the car but even so, you’d still want to keep it in good condition.
Fuel filler necks may be damaged over time and may cause gas leakage. Its replacement is not usually a common thing during maintenance services, but it is an essential job since the filler neck plays an important role in the vehicle’s fuel system.
Fuel Filler Neck Replacement or Repair?
The price of a fuel filler neck replacement usually depends on the type, model, and age of your car. Parts usually range from $40 to $300, but they can cost more especially if you include the labor fee.
You can opt for short-term DIY fixes for leaks using seal-alls, exhaust bandages or fiberglass since most shops offer replacements and not repairs. However, in the long run, you could save more with a replacement compared to the possible fuel filler neck repair cost.
Here are some quoted prices for having the fuel filler neck replaced in some popular car models. You can also ask your preferred auto parts shop and dealership if you only want to purchase the neck itself.
To give you an idea how much this job entails for some vehicle models, we’ve consulted one of the popular auto service centers online:
|2003 Nissan Sentra||$193||$70||$263|
|2005 Cadillac STS||$76||$70||$146|
|2007 Chevrolet Cobalt||$127||$91||$218|
|2008 BMW 535i||$870||$546||$1,416|
|2009 Ford Mustang||$175||$98||$273|
|2009 Mitsubishi Galant||$148||$70||$218|
What is a Fuel Filler Neck?
The fuel filler neck is a solid piece of tubular component that joins the fuel filler inlet or gas cap and the rubber fuel fill hose on the gas tank. It is created in a 45º angle so it is easier to get the fuel in the tank.
Some tank filler necks also have an upper and lower collar seals that prevent gas fumes from entering the cabin. The upper seal, which is on top of the fuel neck, seals against the back side of the fender behind the taillight. Furthermore, the collar secures the filler neck where it is attached through the rear fender splash panel on the trunk floor.
There is a soldered metal hose or a clamp around the rubber hose that connects the neck to the gas tank. It seals the fuel filler neck and also prevents any fuel leakage.
Inside the fuel filler neck is a one-way valve that keeps foreign objects like water and other contaminants from entering the fuel tank. It ensures that only fuel can get into the engine. This siphon hose-like component also keeps out the harmful objects that may cause the vehicle’s fuel tank to wear out faster.
In older vehicles, the fuel tank has a short fuel filler neck and a metal tube. It is also joined with a long rubber hose with two clamps.
On the other hand, a lot of modern and newer cars contain a tube that is attached to the fuel tank at one hole and the filler neck on the other that is close to the gas cap opening. Whenever the tank overflows, this pipe takes the fuel back into the filler neck in order to turn off the gas pump nozzle.
Fuel filler necks can be metal, usually made of lightweight aluminum, steel or chrome plating; sometimes even rubber.
Newer fuel filler necks are powder-coated and are made using premium materials which make the necks durable enough to withstand the corrosive effects of the harsh environment it’s regularly exposed to. Even though they have tough exteriors that marginally increase their lifespan, they are still prone to damage.
What About the Fuel Filler Hose?
Some fuel filler necks are directly attached to the fuel tank. However, in most cars, the neck is connected to the tank with a hose. It is usually made with durable rubber or neoprene that should withstand extreme temperatures and pressures and the hose is secured to the neck with clamps.
Fuel filler hoses can be flexible and can bend in 45 or 90 degrees or straight. You should consult your car’s manual for the right length and circumference when buying fuel filler hoses.
Hoses can be used in the main tank or the auxiliary tank. When purchasing hoses, always be specific because hoses for the main and auxiliary tanks are not the same.
When checking for leaks in your fuel filler neck, make sure to also check the hoses. In some cases, the problem can be found at the hose and not the neck. Fuel filler hoses are as important as the fuel filler necks.
Symptoms of a Bad Fuel Filler Neck – When Should You Replace It?
Even though they are made to be long-lasting, prolonged interaction with dust and corrosive chemicals can cause the filler necks to wear and rust over time.
They usually develop holes and cracks that allow the gas to leak out. You might notice significantly lower gas mileage if the leak causes the fuel to drip continuously.
It can be very dangerous even though liquid fuel doesn’t burn. What makes it flammable is the vapor from the fuel. Friction from the rocks or from anything under the vehicle can induce a spark that might ignite.
These cracks and holes are not only possible fire hazards, but they also allow dust and debris to penetrate inside the tank. In turn, this will reduce the performance of the engine. The fuel filler neck can also take damage from accidents and collisions.
If you don’t have the time, they can be temporarily patched with adhesives available at auto shops but if you want to avoid future problems, replacement is a better long-term fix.
It also might be a good idea to replace your fuel filler neck if ever you notice rusts forming on it. Prolonged exposure to water and mud can cause filler neck decay.
Another symptom commonly found on a failing fuel filler neck is the smell of fuel. If you ever notice the lingering smell of fuel that becomes stronger over time even if you’re not filling the tank up, that could be a sign that the fuel filler neck might have a small leakage.
Aside from this, a filler neck that is leaking vapors can cause issues with the car’s EVAP system. Usually, the Check Engine Light illuminates to notify you whenever it detects an issue with the system.
An illuminated Check Engine Light means that there might be an underlying problem caused by other factors. It is better to check the trouble codes to be sure. Below are some of the codes that you may encounter over time.
|P0440||Evaporative Emission Control System Fault|
|P0441||Evaporative Emission Control System Incorrect Purge Flow|
|P0442||EVAP Emission Control System Leak Detected (small leak)|
|P0443||EVAP Emission Control System Purge Control Valve Circuit|
|P0444||EVAP Purge Control Valve Circuit Open|
|P0445||EVAP Purge Control Valve Circuit Shorted|
|P0446||Evaporative Emission Control System Vent Control Circuit|
|P0447||EVAP Emission Control System Vent Control Circuit Open|
|P0448||EVAP Emission Control System Vent Control Circuit Shorted|
|P0449||EVAP Emission Control System Vent Valve/Solenoid Circuit|
|P0450||Evaporative Emission Control System Pressure Sensor|
|P0451||EVAP Emission Control System Pressure Sensor|
|P0452||EVAP Emission Control System Pressure Sensor Low Input|
|P0453||EVAP Emission Control System Pressure Sensor High input|
|P0454||EVAP Emission Control System Pressure Sensor Intermittent|
|P0455||EVAP Emission Control System Leak Detected (gross leak)|
|P0456||EVAP Emission Control System Leak Detected (small leak)|
|P0457||EVAP Emission Control System Leak Detected (fuel cap)|
Fuel or vapor leaks could also result in a failed emissions inspection. So whenever any of these symptoms occur, a fuel filler neck replacement might be necessary.