The likely issue with any fuel filter is chiefly incorrect maintenance. Fuel filters can start to cause issues if the correct service schedule isn't adhered to. On most 21st century cars, they typically don’t need to be changed and are mounted in the tank with the fuel pump. On cars with an external filter, they are typically replaced every 30k miles.
So if you don't know the last time the filter was changed on an older car – change it as soon as you can. Clean fuel and a free flowing filter has a huge bearing on how well your car runs, and as they aren't hard or expensive to replace there's no excuse.
External filter housings, or connections can at times leak – or allow air into the system. Both of these can cause running, and starting issues, so it's well worth checking them if you have problems, such as poor starting, hesitant acceleration, or the engine 'dying' at low rpm.
While on most vehicles changing the filter is straightforward – on other cars, (mainly diesel trucks) you often have to fill the filter housing with fresh fuel, or use a hand pump to draw fuel through the system when you swap filters, otherwise it will be difficult, or even impossible to start.
Trying to start some vehicles without fuel in the system can cause damage to the fuel pump, as the fuel also acts as a lubricant – so if after changing the filter the car refuses to start – don't be tempted to keep cranking it over, as you could find yourself needing a new fuel pump!
What tools do you need to replace a fuel filter?
You should only need basic tools to replace the filter – but if your vehicle requires the filter to be 'primed' prior to use then you will need to invest in a primer/hand pump. These aren't particularly expensive, and it's always worth checking to see if you'll require one for your filter swap.
If you are dealing with a car that has the filter in the tank, it is more complicated. Be prepared to pump the fuel out of the tank, or lower a heavy tank of fuel. In-tank filters are sometime integral with the pump, but even if they aren’t, it is a good idea to replace the pump, and the pre-filter strainer while the tank is out.
How to extend the life of your fuel filter
There is never a good reason to attempt to extend the service life of the fuel filter.
One thing you can do is always buy branded gas from a reputable station, and never get gas while the tanker is delivering fuel. Avoiding dirty gas and sediment will keep the filter clean and the fuel pump in good condition.
How long should a fuel filter last?
Filters should generally be replaced between 20-40,000 miles – although your owner’s manual will have the suggested replacement intervals. If the filter is in the tank, there often is no suggested replacement interval.
It's not a bad idea to replace filters more frequently than the recommended service schedule states – but having said that many cars run way past their service intervals with the original filter, without issue.
How much does it cost to fix a fuel filter yourself?
Fuel filters aren't expensive – with the most basic in-line filters costing a couple of dollars.
More involved filters may cost up to $50, but in general you're looking around the $10-15 mark. A hand pump/primer (if you need one) shouldn't cost more than $15.
If you are dealing with an in-tank filter and pump combo, you may have to spend several hundred on the replacement parts.