More advanced vehicles such as the PSA vehicles have a built-in additive system. This additive system is consists of a tank and pump which computes automatically the exact amount of additive that needs to be mixed in the diesel fuel. Active type additive system such as this depends on the additive added on the fuel to decrease the soot particles’ ignition temperature. With the help of a management system for the engine, sensors can monitor the filter’s load and automatically start a filter regeneration process by changing the timing of the engine and the settings of the flow of fuel. The additive is initially stored in its own tank and only combines with the fuel during fill up.
Active regeneration
Active regeneration system is possible by the limit set for the load the filter can contain or a built-in sensor reads how much load the filter already has. When the set limit is reached, the timing adjustments on the fuel injection is activated which results in an increase in the temperature of the exhaust. After the temperature has increased, the soot starts to burn which clears the filter and regenerating it.
Passive regeneration
Passive regeneration is preferred by some of the manufacturers. Passive regeneration on vehicles is usually done on the motorway because the temperature of the exhaust is higher there. Systems that are employing the passive regeneration contain integrated oxidising for catalytic conversion. It is usually located near the engine because the gases of the exhaust are hotter there which makes passive regeneration an ideal method. The temperature of the exhaust needs to be high for passive generation to work which is necessary in burning automatically the particles. It should be done on the motorway because passive regenerating on short trips could block the filter if not done fully after a short driving time. This may result to high consumption of fuel and may merit a visit to the mechanic so the filter may be cleaned or even replaced.
Forced regeneration
Forced regeneration is done on a garage because it needs a computer program to make the car run. The program will then start a regeneration of the diesel particulate filter. Forced regeneration are usually needed when a vehicle went to limp mode. After forced regeneration, the engine oil and the oil filter must be changed.