Following your owner’s manual recommendations is a key to trouble-free long-lasting performance of your vehicle. One of them is replacing your fuel filter according to recommended change intervals. A dirty fuel filter may cause a lot of engine problems including rough idling and poor acceleration. Here are common signs of a bad fuel filter.
Your engine is hard to start
Different contaminants collecting inside the filter may restrict the fuel flow which makes it harder to start the engine. Your starter will have to do a lot of cranking to begin the combustion process. If this happens, the fuel filter is the first thing you should check.
The restricted fuel flow due to your dirty filter may cause the engine to hesitate when accelerating or starting from a place. Depending on the condition of the filter, you may experience some bucking or stumbling when engaging the gas pedal. This unexpected behavior of your vehicle may lead to serious troubles on the road and cause an accident.
Misfiring and a lack of performance
Due to a poor fuel filter, your engine will experience a lack of fuel supply, so it will not be able to produce as much power as it should especially at higher RPMs. This will result in engine misfiring along with its jerking and stuttering.
Check engine light is on
Your fuel filter does not communicate with the engine control module, however, problems caused by a bad fuel filter can trigger an array of trouble codes, such as:
- Low fuel pressure and lean air/fuel mixture
- Fault of the oxygen sensor or mass air flow sensor
- Engine misfiring
If the check engine light turns on, the first thing that should be checked before replacing other engine parts is the condition of the fuel filter.
If your fuel filter allows just enough fuel for starting the engine and idling, however, its amount is not enough for acceleration and cruising, the engine may start perfectly, but will stall once you press the gas pedal. Sometimes, the flow of fuel can be intermittent, causing occasional engine stalling.
Your engine doesn’t start
No fuel means no start. If the fuel filter is completely clogged, the starter will crank, but never start the engine.
Lack of power at some speeds
A dirty fuel filter may perform perfectly at higher speeds when the higher fuel pressure inside the system negotiates problems caused by a bad filter. However, at lower speeds the pressure reduces and cannot overcome the restriction.
This happens due to the same reason as described above. The restricted fuel flow doesn’t allow enough gas for smooth engine idling. If so, the engine can vibrate, and your tachometer’s needle can move erratically.
All you need to know about a fuel filter
The job of a fuel filter is to prevent any aliens that may get into the system with fuel from entering the engine, while not restricting the fuel flow. Ignoring fuel filter change intervals will lead to collecting an excessive amount of dirt and other particles that may potentially reach your fuel injectors and cause their damage.
Depending on the design of your vehicle, its fuel filter can be found under the hood, somewhere between the engine and the fuel tank. Sometimes, it may be located inside the fuel tank or underneath the vehicle.
By itself, gasoline is spotless. However, being stored, transported and then pumped into your car or truck, it provides a chance for different contaminants to get onboard and hit your engine. Your fuel filter removes all particles that try to reach the motor and cause damage to its perfectly machined surfaces or your fuel injectors.
The design of a fuel filter is quite simple. It features a pleated material that blocks the debris, while allowing clean fuel to go through it to the injectors.
Fuel filter maintenance
Both fuel filter and fuel pump should be tested before replacing the filter.
A poor filter is not repairable and should be replaced. Fortunately, it is usually not expensive, so it will not cost a bomb. If the replacement is done by a technician, he or she may provide complex testing to determine all existing and potential problems based on the type of contaminants found in the filter and the fuel system.
The majority of vehicles produced in the past decades feature quick release fittings applied to the filter to withstand high pressure. They are easy to remove using correct tools for the type of fittings you have.