In this article, we’ll be talking about bad fuel filter symptoms.
The fuel filter is an immensely important part of your car. If it’s not replaced on time it can cause big problems like the engine not starting or even damage the fuel intake system.
So, noticing bad fuel filter symptoms on time is crucial both for your engine and for avoiding costly repairs.
We’ll be showing this on the Skoda Fabia but all of these symptoms are present more or less, in whatever car you drive.
Besides this article, you can watch our video on this same topic on our YouTube channel.
ABOUT THE FUEL FILTER
Just a few words about the importance of the fuel filter on your car.
The fuel filter has the role of keeping the fuel clean so any accidental debris doesn’t get into the fuel intake system.
If it did, it could cause a lot of expensive damage. On most cars, any of the fuel intake components are pretty expensive and this is one of the main reasons why changing the fuel filter on time is of great importance.
Also, if the fuel filter gets clogged, the fuel pressure in the system is seriously reduced depriving the engine of the needed fuel. Besides this, enormous pressure is put on the fuel pump since much more pressure is needed to push the fuel through the system.
Regarding cost, in the majority of cases, the fuel filter is not expensive to buy and replace.
For instance, the fuel filter for this Fabia is about 20 euros (in my country) and lasts on average for about 30000 miles or about 50000 kilometers.
Replacing it is pretty simple and fast so even if you pay a garage to do it it shouldn’t cost that much.
So, all in all, the fuel filter is a small, simple, cheap yet very important part of your car.
BAD FUEL FILTER SYMPTOMS
1. ENGINE STALLS AND LOSES POWER
The first and most obvious symptom of a bad fuel filter is that you’ll notice the engine starts losing power.
At first, it will be barely noticeable while later it becomes a constant problem.
In most cases, you’ll notice a sluggish response on the gas pedal and a growing delay in the throttle response.
It much resembles driving a car with deflated tires.
2. THE ENGINE NEEDS LOTS OF CRANKING TO START
The next symptom is that the engine starts heavily and needs a lot of cranking.
At first, you’ll notice a slightly longer cranking than usual or it may take a couple of turns of the key to start.
Later as the problem progresses the car will start harder and harder and eventually will not be able to start at all.
This is one of the bad fuel filter symptoms that is especially present with diesel engines when the filter is clogged and goes double during the winter season.
3. ROUGH IDLING
At this point, you should notice one more of the bad fuel filter symptoms.
This would be rough idling. It sounds much like if there was a bad throttle body on your car.
If you want to see more on the symptoms of a bad throttle body click here to see a specific article on that topic or watch the YouTube video.
Just like with other symptoms, rough idling may be barely present in the beginning while later it will become always present.
4. PERIODIC ENGINE MISFIRE
Besides rough idling, you may experience periodic misfires of the engine.
It sounds much like when a spark plug or coil pack isn’t working properly.
This usually happens in the final phase, when the engine starts having serious issues with the fuel flow and the filter is seriously clogged.
For more information about engine misfires click here.
5. WHINING FUEL PUMP NOISE
As mentioned, if you disregard a fuel filter problem you may cause damage to other components of the fuel intake system.
Mainly to the fuel pump which has to produce much higher pressure in order to maintain the needed fuel flow to the engine.
Because of this abnormal pressure, you may hear a distinct whining sound from the pump.
Since the pump is usually located at the rear of the car near or inside the fuel tank the sound comes from the back of the car and otherwise is not present.
Besides the pump, a bad fuel filter can also cause damage to the components like the injectors for instance.
Noticing bad fuel filter symptoms on time is very important if you want to prevent more serious damage.
The moment you notice any of the mentioned symptoms take action and make an inspection.
Perhaps even more important, monitor the maintenance intervals on your car and pay attention to them.
If the fuel filter is changed within the intervals recommended by the car manufacturer, you’ll almost certainly avoid problems.
Also, if you doubt the quality of fuel in your country make sure to change the filter more frequently.
Don’t be cheap and reckless, replacing the fuel filter is a small investment but one that keeps the expensive fuel intake components from harm’s way.
This advice goes double for more expensive cars.
Written by: Sibin Spasojevic
Former car technician, life-long car and DIY enthusiast, author for Despairrepair.com