symptoms of a bad fuel filter

Symptoms Of A Bad Fuel Filter: 6 Signs To Monitor

All parts in the car have an essential function to do in order for the car to function well. This is why there is a need to check these parts from time to time and act on the necessary repairs and replacements to avoid worse case problems in the later part. Again, this is already familiar to you: Preventive maintenance. One important part to monitor is the fuel filter. In layman’s terms, a fuel filter aids in screening rust, dirt and other unnecessary particles to enter into your engine which may cause damage. If left unchecked for so long, this may result to having a bad fuel filter. With this, certain signs may start to appear. Explained in this article are some of the symptoms of a bad fuel filter that we should take note and avoid.

Although small in size, fuel filters play a big role in the fuel management systems. It protects your fuel pump and injectors from being contaminated by particles such as dirt and rust, for example. Depending on your auto manufacturer’s recommendation, replace the fuel filter when needed. However, there are times that we forget or just take this for granted that’s why problems occur in the later part. If ever this may happen, below are the six signs you need to change your fuel filterand after confirming that these signs are evident in your car, you may consider articles on how to check fuel filter.

Low Engine Power

Technically upon cranking, the engine should not struggle. But in this case, the engine power is low. One of the major reasons for this issue is a fuel filter not working well. In order for your car to start running, the engine must have enough power which is provided by the fuel that goes into the fuel filter to remove all the unwanted particles and finally reaching down to your fuel pump and injectors. Your filter may be clogged with these particles causing lesser fuel delivered into your engine. Fuel restriction or inconsistent fuel flow are some of the effects of having a bad filter.

Engine Sputtering

When driving especially on a highway, engine sputtering may cause accidents that would mean safety issues and may risk lives. Due to the erratic flow of the fuel, the engine will sputter because it depends on how much fuel it can get to keep running. This may vary in different speeds and RPM but regardless of that, this should be avoided.

Failing Fuel Management System

It’s the domino effect. Once a part breaks down, the rest of the entire system are all affected. This is inevitable especially for fuel management systems. In order for a certain part to function, the other one must function well too. But if not, then the system will fail. In the case of a failing fuel pump, there lies corresponding problems which requires troubleshooting from expert automotive mechanics. This may even cost a lot of money if the problem is really worse. The fuel filter can be replaced and can be done by mechanics, but if you want to do it on your own, make sure you know how to do it and just prepare the necessary tools for this activity.

Bad Fuel Filter Sound – Engine Knocking

After warming up your car, hearing up that unusual knocking sound coming somewhere from your engine is not a good sign. The reason for that is again a damaged fuel filter. Turn off your car and let it cool down for a few minutes and immediately check on that. 

Check Engine Light/Indicator On The Cluster Is Turned On

One of the things that you don’t want to see turned on in your cluster is the check engine light/indicator. This means a serious problem. You don’t want to drive while having that light turned on. The immediate thing to do is call a mechanic. Or yet, if you know how to diagnose your car, then you can do it on your own. Some cars nowadays already include sensors which could easily detect abnormalities in your car and that is represented by the indicators on your cluster. If the pressure is low, the sensors have sent a signal to the cluster to give a warning to driver; this leads us to the confirmation that there is really something wrong with the fuel filter. Address the issue immediately and don’t wait any further.

Fuel Pump Is Broken

The function of a fuel pump is to draw fuel from the fuel tank which passes through the fuel line and fuel rail to be injected into the cylinder. If this is damaged, this may probably be caused by the damaged fuel filter giving a lot of pressure on the fuel pump; this inhibits the engine to receive a proper amount of fuel coming from the fuel tank.


Considering all the symptoms of a bad fuel filter, it has clearly informed us of the different reasons why. Car manuals usually indicate if that fuel filter is enough for that car in a lifetime, or may indicate if that is only applicable for how many thousand miles and upon reaching the threshold, it should be replaced. It’s best to always refer to the car manual for more information. Some fuel filters by design could last for 100,000 miles only, and some could last a lifetime.

Regardless of what’s stated in the car manual, it is always important to observe preventive maintenance as what I’ve mentioned earlier. To avoid losses, accidents and bigger costs in the later part, carefully monitor your car’s health. Regularly observe the behavior of your car; seek immediate help from automotive mechanics if such conditions arise.