Mphete ya Pistoni ndi mphete yachitsulo yomwe imayikidwa mu payipi ya pistoni. Pali mitundu iwiri ya mphete za pistoni: mphete yokakamiza ndi mphete yamafuta. Mphete yokakamiza ingagwiritsidwe ntchito kutseka mpweya wosakaniza womwe umayaka m'chipinda choyaka. Mphete yamafuta imagwiritsidwa ntchito kukanda mafuta ochulukirapo kuchokera mu silinda.
Mphete ya pistoni ndi mtundu wa mphete yachitsulo yotanuka yokhala ndi mawonekedwe akuluakulu otambasuka akunja. Imasonkhanitsidwa mu mtsempha wozungulira wofanana ndi mbiri. Mphete za pistoni zobwerezabwereza komanso zozungulira zimadalira kusiyana kwa mphamvu pakati pa mpweya kapena madzi kuti apange chisindikizo pakati pa bwalo lakunja la mphete ndi silinda ndi mbali imodzi ya mphete ndi mtsempha.
Mphete ya pistoni ndiye gawo lalikulu la injini yamafuta. Imatseka mpweya wamafuta pamodzi ndi silinda, pistoni ndi khoma la silinda. Mainjini agalimoto omwe amagwiritsidwa ntchito kwambiri amakhala ndi mitundu iwiri ya injini ya dizilo ndi petulo, chifukwa cha magwiridwe antchito amafuta ake ndi osiyana, kugwiritsa ntchito mphete za pistoni sikofanana, mphete yoyambirira ya pistoni pogwiritsa ntchito kuponyera, koma ndi kupita patsogolo kwaukadaulo, mphete ya pistoni yachitsulo yamphamvu kwambiri idabadwa, ndipo ndi kusintha kosalekeza kwa ntchito ya injini, zofunikira zachilengedwe, mitundu yosiyanasiyana ya ntchito zochizira pamwamba, monga kupopera kutentha, electroplating, chrome plating, Gas nitriding, physical deposition, surface coating, zinc manganese phosphating treatment, kotero kuti ntchito ya mphete ya pistoni imakula kwambiri.
