The Particulate Filter (FAP) is a key component of the exhaust system. It helps to limit pollutant emissions while ensuring the engine runs smoothly.
However, over time and with use, it can gradually become clogged, often without any obvious symptoms at first.
Knowing how to recognise the signs of a clogged FAP allows you to take action at the right time, before the situation turns into a costly breakdown. Here are the indicators to watch out for.
The engine warning light: one of the first signs of a clogged FAP
Firstly, the engine warning light or FAP warning light coming on is often the first warning sign.
At first, it may appear occasionally, then become more frequent. This behaviour usually indicates a problem with the proper evacuation of exhaust gases, a direct consequence of a filter that is starting to become saturated.
Loss of power, a typical sign of a clogged FAP
Next, a gradual decline in performance may become noticeable. The engine becomes less responsive, particularly when accelerating or climbing hills.
This is because a clogged FAP restricts the flow of gases, forcing the engine to operate under suboptimal conditions. This loss of power is often a sign that the problem is developing.
Increased fuel consumption, one of the signs of a clogged FAP
Furthermore, an engine that compensates for a clogged particulate filter consumes more fuel.
If you notice an unusual increase in fuel consumption without any change in driving habits, this may indicate an imbalance caused by a clogged filter. This symptom is sometimes underestimated, even though it is a reliable indicator.
Repeated regeneration cycles: a clear sign of a clogged FAP
In addition, regeneration phases often become more frequent. The vehicle then attempts to burn off the accumulated particles to clean the FAP.
When these regenerations become more frequent or fail, it is usually a sign that the clogging exceeds what the system can handle on its own.
Degraded mode, the final sign of a clogged FAP before failure
Finally, when saturation becomes too high, the vehicle may switch to degraded mode.
This safety feature deliberately limits performance in order to protect the engine. At this stage, urgent action is required, as ignoring this signal may result in more serious damage.
Take action at the first signs of a clogged FAP
In summary, the signs of a clogged DPF appear gradually and provide a real opportunity to take action before a breakdown occurs. Early intervention often avoids costly replacement and vehicle downtime.
At Sud Ouest Radiateurs, we favour a preventive approach and solutions tailored to each situation.
👉 Do you recognise one or more of these signs?
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