The likely issues you may face with fuel filters are chiefly to do with incorrect maintenance. Fuel filters can start to cause issues if the correct service schedule isn't adhered to.
So if you don't know the last time the filter was changed – change it as soon as you can. It has a huge bearing on how well your car runs, and as they aren't hard or expensive to replace then there's no excuse.
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 yours 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 diesels) you often have to either fill the filter housing with fresh fuel when you swap filters, or use a hand pump to draw fuel through the system, otherwise the car will be difficult, or even impossible to start.
Trying to start a diesel vehicle without fuel in the system can cause damage to the high pressure 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.
Attempting to start a car that needs to be 'primed' first can cause damage to the pump.
How to extend the life of your fuel filter
There is never a good reason to attempt to extend the life of the fuel filter.
The service schedule should always be adhered to, and it's no bad thing if you decide to change it more often than the schedule suggests.
Get a decent quality brand, and it's one component where buying from the main dealer is advisable, as opposed to buying an aftermarket version of unknown quality.
How long should a fuel filter last?
Filters should generally be replaced between 20-40,000 miles – although your handbook will have the suggested replacement intervals.
It's not a bad idea to replace them 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 quid.
More involved filters may cost up to £30, but in general you're looking around the £10-15 mark. A hand pump/primer (if you need one) shouldn't cost more than £10.