What happens if a fuel filter is completely blocked?

When a fuel filter becomes completely blocked, it restricts the flow of fuel to the engine. This lack of fuel means the engine cannot receive the necessary amount of fuel to operate effectively. As a result, the engine can eventually stop running altogether. The fuel filter's purpose is to catch dirt, debris, and other contaminants from the fuel before they reach the engine, but when it's blocked, it prevents any fuel from flowing through. This situation leads to a lack of combustion, which is essential for the engine to run, hence causing it to stop.

In contrast, smoother engine operation, improved fuel flow, or overheating do not align with the consequences of a blocked fuel filter. A completely blocked filter cannot contribute positively to engine performance or fuel management, thus confirming that it can indeed cause the engine to stop.