Short journeys make it difficult for the particulate filter to reach the temperature needed for regeneration. The process may be interrupted repeatedly and soot load can gradually increase.
When possible, take a continuous drive with the engine fully warm. Avoid switching off immediately if you notice a higher idle, active cooling fans or changed instant fuel consumption, which may indicate regeneration.
Use oil with the correct manufacturer approval and promptly repair glow-plug, thermostat, injection or sensor faults. Any of these can prevent a successful regeneration.
A motorway drive can help, but it cannot remove accumulated ash or repair an active fault. If warnings or loss of power appear, diagnose the vehicle before pushing it harder.
