Engine system in which a lubrication oil that forms water-soluble ash when combusted is used and a vehicle comprising the engine system

The present invention relates to an engine system (30) comprising:- an internal combustion engine (2) arranged to be operated by a fuel and to be lubricated by means of a lubrication oil that forms water-soluble ash when combusted;an exhaust gas system for cleaning an exhaust gas flow from the internal combustion engine, the exhaust gas system comprising a diesel particulate filter (23) arranged to capture particulate matter from the exhaust gases, wherein the particulate matter comprises the water-soluble ash,- an exhaust gas conduit (11) arranged to lead exhaust gases from the internal combustion engine (2) through the exhaust gas system (10), andinjection means (240) arranged to add an aqueous solution into the exhaust gas flow upstream of the diesel particulate filter (23),wherein the exhaust gas conduit (11) is arranged to collect the added aqueous solution and optionally condensed water formed by the cold operation of the internal combustion engine (2) and lead the total obtained aqueous solution through the diesel particulate filter (23), the total obtained aqueous solution thereby dissolving and thus removing the water-soluble ash from the diesel particulate filter (23). In this way, in-situ cleaning of a diesel particulate filter can be provided.