spark plugs, omwe amadziwika kuti mapulagi oyaka moto, adzagwira ntchito ngati phokoso la piezoelectric lapamwamba kwambiri kuchokera ku nsonga yamoto (moto plug), yomwe idzaphwanya mpweya pakati pa ma electrode a spark plugs, kupanga magetsi kuti awotse kusakaniza kwa gasi mu silinda. Mikhalidwe yoyambira ya injini yogwira ntchito kwambiri: mphamvu yayikulu yokhazikika, kusakaniza kofanana, chiŵerengero chapamwamba cha psinjika. Magalimoto okhala ndi injini zoyatsira mkati nthawi zambiri amagwiritsa ntchito mafuta a petulo ndi dizilo. Pamsika wamagalimoto ku China, magalimoto amafuta amakhala ambiri. Ma injini a petulo ndi osiyana ndi injini za dizilo chifukwa petulo ili ndi malo oyaka kwambiri (pafupifupi madigiri 400), zomwe zimafuna kuyatsa mokakamiza kuti muyatse kusakaniza. Kupyolera mu kumaliseche pakati maelekitirodi kubala zipsera, mafuta injini ndi mwa mafuta ndi gasi osakaniza kuyaka nthawi yake kupanga mphamvu, koma monga mafuta mafuta ngakhale mu malo kutentha ndi zovuta mowiriza kuyaka, kuti kuyaka yake yake m`pofunika kugwiritsa ntchito "moto" kuyatsa. Apa kuyatsa kwa spark ndi ntchito ya "spark plug".
