Fuel entering any vehicle’s engine must first pass through the fuel filter, which is a mesh-like screen accountable for filtering out dirt and debris present in the fuel. Problems with a vehicle fuel filter can cause different common engine performance problems.
For an engine to operate properly, it needs to have a stable supply of fuel all the time. If a fuel filter becomes blocked with dirt or debris, it can significantly hinder the flow of fuel into the vehicle’s engine. This can cause many different engine symptoms, with engine hesitation, or faltering, being chief among them. Engine hesitation is often most pronounced when a vehicle is accelerated from a stop.
An engine that operates rough, or in a jumbled, irregular manner, can be a sign of a fuel filter problem. A rough engine idle can occur when engine combustion is not normal, a condition that negatively affects any engine performance. Abnormal engine performance can be caused, in part, if a plugged or damaged fuel filter severely restricts the flow of fuel into a vehicle’s engine. This can harshly disrupt normal engine air/fuel mixtures, which can cause poor engine performance and a coarse engine idle.
In extreme cases, a bad fuel filter can prevent any vehicle from even getting started. This type of situation mostly happens when a fuel filter becomes completely plugged, thereby completing shutting off fuel flow to the vehicle’s engine, which prevents a vehicle from taking an initiate. A plugged fuel filter is a very common cause of a vehicle no-start condition, especially in older vehicles armed with carburetors.
It is very common for a vehicle with a dirty fuel filter to run perfectly and smoothly at high engine speeds but stall and/or hesitate when the engine speed is comparatively low. This is caused by the differences in fuel flow pressure that is present between high and low engine speeds. When the engine speed is high, fuel pump pressure is stable enough to force engine fuel through the clogged fuel filter and into the engine, allowing the engine to operate in a normal fashion. However, at low engine speeds, fuel flow pressure is not high enough to overcome the fuel filter hindrance, thus causing erratic or bad engine performance.
A common sign of a dirty fuel filter is a vehicle that suddenly dies out regularly while being in operation. This mostly happens when the flow of fuel through a dirty fuel filter alternates between flowing adequately and becoming temporarily obstructed. The vehicle will run when fuel flow is sufficient enough to allow engine processing, but cut out and die when fuel flow becomes completely blocked or severely restricted. The type and amount of dirt within the fuel filter, as well as fuel pump strength can play a major role to this problem.
If you feel that your engine is no more fuel efficient and is also behaving not as it should, it is time to clean or replace your fuel filter.