5 Symptoms of a Clogged Fuel Filter (& Replacement Cost)

When you refuel your car, it follows a lot of dirt and other particles from the gas station into your car's tank, which can clog the fuel filter after a while. Here's how to tell your fuel filter is clogged.

Symptoms Of A Clogged Fuel Filter

The fuel filter is an important part of the fuel supply system of your vehicle.

It ensures that impurities, dirt, particles, dust, objects, and rust cannot enter the fuel and combustion chamber by screening out all these contaminants. Therefore it is very important to change your fuel filter regularly.

The fuel filter can develop problems earlier than we might think, so it is important to know all the signs associated with a failed or clogged fuel filter.

What Are The Symptoms Of A Bad or Clogged Fuel Filter?

The main symptoms of a bad or clogged fuel filter include:

  • Difficulty Starting the Car
  • Misfiring Engine
  • Bad Performance
  • Check Engine Light Illuminates
  • Engine Stalling

While these are the most common signs and a quick look at them, it’s far from all of them. Here is a more detailed list of the signs of a bad or clogged fuel filter to look for:

1. Difficulty Starting the Car

Hard Starting

The first symptom you might notice if your fuel filter is starting to get clogged is difficulty starting the car. The starting moment for a car engine is pretty critical, and a lot of fuel is required.

If the filter is clogged, you may have a tough time trying to start your car if the fuel pressure gets too low.

2. Misfiring Engine

Spark Plug Misfires

If fuel only intermittently gets into the engine, it can lead to low fuel pressure, which often leads to misfiring and other hiccups.

You can feel engine misfires as small jerks when you are accelerating your car, but also on idle. If you notice many misfires when accelerating your car, it is definitely time to check when your filter was replaced.

3. Bad Performance

Poor Acceleration

A clogged fuel filter leads to low fuel pressure, and as you might know – the engine prefers a lot of fuel for its maximum performance.

If the fuel pressure gets too low, you will probably feel that your car is much slower than usual.

4. Check Engine Light Illuminates

P0420 Check Engine Light

Modern vehicles have sensors placed on every square inch of the car engine and send signals to the car’s computer that tell it if something is wrong.

The computer then illuminates the “Check Engine” light on the dashboard and asks you to have the car checked.

If the fuel filter is faulty, the fuel’s pressure entering the system drops, which alerts the fuel pressure sensor, and the “Check Engine” light comes on.

5. Engine Stalling

Engine Stall E1609780473516

You might also experience your engine stalls when trying to accelerate the car or even on idle.

This is because the fuel pressure drops so low that the engine will be out of fuel and die completely.

How often should you change the fuel filter?

New Vs Old Fuel Filter

The replacement interval differs between car models and fuel type. As a rule of thumb, you should at least change your fuel filter every 37.000 miles (60.000 km) or every 4th year.

Petrol cars do usually have longer replacement intervals and do not get clogged as often as diesel filters.

The fuel filter should be replaced earlier on a few car models, so you should always check your repair manual for the exact replacement interval.

Some cars do not have to replace it that often either. Actually, many cars have a replacement interval for up to 75.000 miles (120.000km) before you need to replace them.

Of course, this does change depending on what type of fuel you fill your car with also. Some countries have worse fuel quality, and then you have to replace it more often.

Fuel Filter Location

Fuel Filter Replacement

The fuel filter is usually located somewhere near the fuel tank, under the car. It can also be located under the hood or somewhere on the way behind the plastic covers under the car.

The fuel filter location can differ a lot, and your best bet to find the location is to check in the engine bay and near the fuel tank under the car.

If you can’t find it, check your repair manual or call your authorized dealer.

Fuel Filter Replacement Cost

The average fuel filter replacement cost is between $30 and $210, depending on the car model and labor costs. The fuel filter can cost between $10 and $60, while labor costs can vary between $20 and $150.

The fuel filter installed in your vehicle is one of those components that require frequent and regular maintenance.

The fuel filter price is usually reasonable, and it can easily be replaced with instructions in the service manual if you have some basic knowledge of car repairs.

The parts required for a replacement will cost you on average between $10 and $60 for most cars.

However, if you are willing to hire a professional or mechanic to do this, there are high additional labor costs.

Checking the Fuel Filter

Fuel Filter FAQs

How do you unclog your fuel filter?

Although you can potentially unclog a fuel filter with compressed air or water, it is not recommended. Fuel filters are pretty cheap and trying to save some money and clean the filter will only lead to more problems. Fuel filters also have a service schedule, so if it’s been a while since it was replaced, you should definitely change it.

Can you drive with a clogged fuel filter?

No, you should not drive with a clogged fuel filter. Your car’s fuel filter is responsible for keeping contaminants out of the fuel system, and if it becomes clogged, fuel can’t flow properly through the system. This can cause all sorts of problems, from decreased performance to higher emissions to complete engine failure. So if your fuel filter is clogged, get it replaced as soon as possible.

Will a clogged fuel filter throw a code?

Yes, a clogged fuel filter can cause an error code. If the fuel filter is clogged, the engine will most likely run lean, causing the ECM to throw a lean air-fuel mixture or misfire related trouble codes. You may see codes like P0171 or P0300.

Can I change my fuel filter myself?

Many fuel filters are fairly easy to change, so with some basic knowledge, it shouldn’t be a problem with most car models. However, on some car models it can be very tricky and you may need to use a repair manual. Remember to use safety equipment as gas is dangerous.

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Magnus Sellén
Written by:

Magnus is the owner and main author of Mechanicbase. He has been working as a car mechanic for over 10 years, and the majority of them specialized in advanced car diagnostics and troubleshooting. Certified Automotive Diagnostic Technician.