The exhaust muffler chitoliro ndi mbali ya injini utsi dongosolo.Dongosolo la utsi ndilofunika kwambiri pakuwononga mafuta komanso chilengedwe.Dongosolo la utsi wagalimoto lidzachotsa mpweya woipa womwe umapangidwa pakuyaka.Dongosolo la utsi silingalepheretse mpweya wowopsa monga carbon monoxide, nitrogen oxides ndi ma hydrocarbons kulowa mu cab, komanso "kuyeretsa" mpweya usanatulutsidwe ku chilengedwe.

Dongosolo la chitoliro chotulutsa utsi makamaka limaphatikizapo utsi wochuluka, chitoliro cha utsi ndi muffler.Nthawi zambiri, chothandizira katatu chowongolera kuwongolera kutulutsa kwa zoipitsa za injini chimayikidwanso muutsi wamagetsi.
Pamene mphamvu ya gasi imatulutsidwa, sikhalanso yamtengo wapatali kwa injini.Mipweya imeneyi imakhala mpweya wotulutsa mpweya ndipo imatulutsidwa mu injini.Pambuyo pa kutuluka kwa silinda, mpweya wotulutsa mpweya umalowa m'kati mwake.