When controller 62 determines that regeneration is complete , controller 62 may adjust {HEAD ~ valve} 22 to reduce {TAIL ~ the amount} of exhaust flowing through second conduit 20 
to reduce
When controller 62 determines that regeneration is complete , controller 62 may adjust { HEAD ~ valve } 22 to reduce { TAIL ~ the amount } of exhaust flowing through second conduit 20
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH