Change Car Fuel Filter
The fuel filter traps the impurities in the fuel system. A clogged filter restricts the fuel flow to the injectors, causing hesitation, loss of power and difficult starting. It is inexpensive, and replacing it is within everyone's reach.
Mainly diesel
The fuel filter is most critical on diesel engines, where it protects the high-pressure pump and the injectors from impurities and water. On modern petrol engines the filter is often built into the in-tank pump and is not replaced separately.
What is the role of the fuel filter?
Located between the tank and the engine, the filter traps the impurities present in the fuel. Over the miles the filter loads up and gradually restricts the fuel supply. On some recent vehicles the filter is built into the tank and can no longer be replaced separately.
When should you change the fuel filter?
Change the filter according to your vehicle's service schedule: generally every 40,000 to 60,000 km or every 2 to 4 years.
Key points for the replacement
Difficulty 1/5
No special tools required. The main difficulty is locating the filter: usually under the vehicle between the tank and the engine.
Priming the system
After replacement, switch the ignition on and off several times without starting to pressurise the injection system. On some vehicles a priming bulb may be needed.
Cost of the part
Between £10 and £30 online. At a garage, allow around £26 for the part, plus 15 to 30 minutes of labour.
Does my vehicle have an accessible filter?
Every petrol car has one, but on some recent models the filter is built into the tank. Check before buying the part.
Signs of a clogged filter
Loss of power
The engine hesitates under acceleration, lacks power on hills or at high revs. The fuel flow is insufficient to feed the injectors properly.
Difficult starting
The engine takes longer to start, especially from cold. The fuel supply is slowed by the blocked filter.
Stalling at low revs
The engine stalls at idle or on deceleration. The residual flow is no longer enough to keep the engine running.
