The fuel pump in a vehicle moves fuel under pressure from the gas tank to the engine, where it is atomized by the fuel injectors. The fuel pump impeller can become worn by sediments or contamination in the fuel system, and the fine passages in the fuel injector’s spray ports are easily clogged or worn by any foreign material in the fuel.
Because of this, a filter is used to make sure the fuel is as clean as possible. Over time, a fuel filter can pick up enough material to become clogged and restrict the flow of fuel, which then leads to problems with fuel pressure and normal engine operation.
If a fuel filter is clogged, a vehicle can often idle normally, as the least fuel flow is required then. More commonly, the first signs of a fuel filter issue would be symptoms of hesitation, low power, or poor fuel mileage under heavy loads or acceleration. It can also be at highway speeds when fuel consumption and higher flow rates are necessary. There are two main kinds of fuel filters; inline and in-tank.
Cost of Inline Fuel Filter Replacement
Inline fuel filters are located somewhere along the fuel lines; after the fuel is pumped from the tank and before it reaches the injectors. This kind of filter is usually considered a maintenance item and has a specific replacement interval.
On average, for most vehicles using this kind of system, it costs about $75 to replace an inline fuel filter.
The average recommendations range from 30,000 miles to 60,000 miles. An exception would be on some diesel engines, such as the Cummins turbodiesel used in Ram trucks, which has a 15,000-mile service interval. Inline fuel filters are usually located where they can be relatively easily accessed.
Some specific examples of the cost of replacing an inline fuel filter for some common vehicles using $150 an hour as a labor rate are as follows:
| Car Model | Labor Time & Cost | Aftermarket Fuel Filter Cost (Excl. Labor) | Factory Fuel Filter Cost (Excl. Labor) |
|---|---|---|---|
| 2004 Subaru Legacy with a 2.5-liter engine | $120 (0.8 hrs) | a Wix part costs about $19 | $43 |
| 2006 Volkswagen Golf with a 2.0-liter engine | $60 (0.4 hrs) | a Bosch part costs about $14 | $60 |
| 2003 Ford F150 with a 5.4-liter engine | $90 (0.6 hrs) | a Fram filter costs about $16 | $49 |
Cost of In-Tank Fuel Filters
On newer passenger vehicles, an in-tank fuel filter is more common, placed on the fuel pump intake inside the fuel tank. One of the reasons to have the filter before the pump is to protect the pump itself from contaminants.
The drawback, of course, is the difficulty of replacing the filter, which involves removing the fuel pump. In many cases, it’s necessary to remove the fuel tank in order to access the fuel pump. For that reason, in-tank fuel filters have no service or maintenance interval.
In most cases, if an in-tank filter is suspected due to a fuel pressure problem, there’s no practical way to tell before removal whether it is the fuel pump or the filter that is to blame. As with many things where labor is significant or if diagnosis involves the removal of the part, in practice, the fuel pump and fuel filter are usually replaced at the same time if either one is suspected.
On average, if the filter is replaced with the fuel pump, the cost for most vehicles is about $450.
On average, if the filter is replaced with the fuel pump, the cost for most vehicles is about $450.
Related article: Fuel Pump Replacement Cost Guide
For some specific examples, using $150 as a labor rate:
- 2011 Chevrolet Cruze with a 1.8-liter engine
The fuel filter is part of and replaced with the fuel pump module. The labor time for that is 2.1 hours, which includes removing the fuel tank. A factory fuel pump assembly costs about $424, and a Carter replacement part costs about $298. The total cost to complete the job would be about $739 using OE parts, or about $613 using aftermarket parts.
- 2008 Nissan Altima with a 2.5-liter engine
The fuel filter is also part of and replaced with the fuel pump. It is accessed through an opening under the rear seat, and the labor time is around 0.8 of an hour. A factory assembly costs about $508, and a Delphi part costs about $390. This makes the job cost about $628 using OE parts, or about $510 using aftermarket parts.
On the less expensive side are vehicles where there is an access port for the pump, so the tank doesn’t need to be removed, and the in-tank filter can be replaced by itself. For one example of that:
- 2002 Toyota Camry with a 2.4-liter engine
The labor time to replace the fuel filter is estimated at 0.8 of an hour. It’s in the fuel tank but is reached through an access panel under the rear seat. A factory filter costs about $20, and a Beck/Arnley part costs about $24. This makes the job cost about $140 using OE parts or about $144 using aftermarket parts.
Problems That Can Be Caused by a Bad Fuel Filter
In normal operation, fuel is pumped from the tank and then arrives at the fuel injectors at a certain pressure. A restricted fuel filter leads to too much pressure before it and too little pressure after it. That causes the engine to run lean initially, then not run at all eventually. A fuel pump that is trying to push fuel through a blocked fuel filter has to work harder than it was intended to, and that can cause the pump to fail. It’s not uncommon to replace a blocked fuel filter, then find that the vehicle still won’t run and needs a fuel pump as well.
An engine that runs lean will see higher combustion chamber temperatures, which can shorten the life of spark plugs and damage the valves in the cylinder head. A too-lean mixture may not fire at all, which can then send unburned fuel down into the catalytic converter. Unburned fuel in the catalytic converter can cause it to overheat and melt down.
FAQ
Most manufacturers say about every 30,000 to 60,000 miles for an inline fuel filter. That can also vary depending on the quality of fuel used; whether it is well filtered at the pump, for instance.
It’s best to go by mileage, or if that is unknown, just replace the filter before problems occur. But the first symptom of a restricted fuel filter is often a feeling of low power on acceleration or on the highway. It can usually be confirmed with a fuel pressure gauge.
It depends. On some vehicles, the fuel filter is in the engine bay and is pretty simple to replace. More often, it is either tucked underneath the vehicle and requires special tools or is in the fuel tank.
A bad fuel filter will mean a poorly running engine, which can eventually cause expensive problems, so it’s not a good idea. Especially considering how relatively inexpensive a fuel filter is.
One common way is to remove the replaceable filter canister, clean the ends, and try to blow through it in the direction of fuel flow. There will be just a little bit of resistance in a good fuel filter, but a lot of resistance through a blocked fuel filter. In shops doing diagnosis, this was a common check, especially if the fuel filter was easy to access.