Doser Valve

The doser is used only during active regeneration when the TRU engine is too lightly loaded for passive regeneration to occur.

During active regeneration, the doser valve injects a fine mist of fuel into the exhaust stream, where it then ignites on the surface of the DOC to raise the exhaust temperature and oxidize the particulate matter in the CDPF.

The Doser assembly also includes a fuel pump and filter.