The reducing agent is pumped out of a reactant reservoir and to a dosing valve so that after the dosing valve is opened, {HEAD ~ the reducing agent} can be introduced into the engines exhaust gas line in {TAIL ~ a dosed manner} 
The reducing agent is pumped out of a reactant reservoir and to a dosing valve so that after the dosing valve is opened , { HEAD ~ the reducing agent } can be introduced into the engines exhaust gas line in { TAIL ~ a dosed manner }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL