A fuel filter is necessary to prevent dirt and other debris from clogging a vehicle's fuel delivery system, a condition that severely disrupts engine performance. Fuel filters can themselves become clogged, and when that happens, engine power and performance are negatively affected.
If a fuel filter is totally blocked or clogged to the point of blocking fuel flow to a vehicle's engine, the vehicle will not start. Fuel combined with air is what is ignited inside a vehicle's engine to get it started.
A partially blocked or clogged fuel filter will often result in a vehicle that is hard to start. Adequate fuel flow to a vehicle's engine is needed to produce engine starting. A reduced or restricted fuel flow to a vehicle's engine will hinder normal starting.
Frequent Engine Stalling
For a vehicle's engine to run efficiently and adequately, a constant flow of fuel needs to reach the engine. Any disruption of this fuel flow, which is what happens when a fuel filter is clogged, can cause an engine to frequently stall.
Engine hesitation is a common symptom of a clogged fuel filter. By causing an abnormal fuel flow to a vehicle's engine, a condition that results in abnormal engine combustion and reduced engine power, a clogged fuel filter can cause an engine to hesitate or stumble during acceleration.
Erratic Engine Performance
A clogged fuel filter often results in erratic engine performance by causing an abnormal or alternating pattern of fuel flow into a vehicle's engine. Under heavy acceleration or at high engine speeds, fuel pressure may be sufficient to allow adequate fuel flow past a partially clogged filter, which results inadequate engine performance. When engine speed is reduced, fuel flow may be restricted to the point of causing reduced engine power and performance.