Injin firikwensin injin
Siginar sa yana ɗaya daga cikin mahimman sigogi a kan tushen wanda sashin kula da injin yana ƙididdige ƙimar lokacin kunna wuta nan take da adadin man da aka yi masa allura.
A cikin motocin zamani, ana auna zafin injin ta hanyar firikwensin juriya na NTC da ke ciki 
injin sanyaya. Gajartawar NTC tana tsaye ga Ƙunƙarar Zazzaɓi mara kyau, watau. a cikin irin wannan firikwensin, juriyarsa yana raguwa tare da ƙara yawan zafin jiki.
Zazzabi sigar gyara ce don ƙididdige lokacin kunna wuta ta sashin sarrafa injin. Idan babu bayanin zafin injin injin, ana amfani da ƙimar wakili don ƙididdigewa, yawanci 80 - 110 digiri Celsius. A wannan yanayin, lokacin kunnawa yana raguwa. Ta wannan hanyar injin yana kare shi daga yin nauyi, amma aikinsa yana raguwa.
Matsakaicin allura na asali, wanda aka ƙaddara dangane da saurin injin da nauyi, a cikin lokacin farawa sanyi, da kuma sauran yanayin aiki, dole ne a daidaita shi daidai. An daidaita abun da ke cikin cakuda, a tsakanin sauran abubuwa, bisa ga siginar daga firikwensin zafin jiki na injin. Idan babu shi, ana ɗaukar ƙimar zafin jiki maimakon ƙididdigewa, kamar yadda yake a cikin yanayin sarrafa kunnawa. Koyaya, wannan na iya haifar da farawa mai wahala (wani lokaci ma ba zai yuwu ba) da rashin daidaituwar aiki na sashin tuƙi yayin dumama. Wannan saboda yawan zafin jiki na maye gurbin yawanci yana nufin injin da ya rigaya ya dumi.
Idan babu wani abin da zai maye gurbinsa, ko kuma akwai gajeriyar da'ira a cikin da'irar, to ba a wadatar da wannan cakuda ba, saboda gajeriyar kewayawa, watau. ƙananan juriya na kewayawa, yayi daidai da injin zafi (juriyawar firikwensin NTC yana raguwa tare da ƙara yawan zafin jiki). Bi da bi, bude kewaye, i.e. tsayin daka mara iyaka, mai kulawa yana karantawa azaman yanayin matsananciyar sanyaya injin, yana haifar da matsakaicin yuwuwar wadatar adadin man fetur.
Nau'in firikwensin nau'in NTC yana aiki da kyau ta hanyar auna juriyarsa, zai fi dacewa a wurare da yawa a cikin halayensa. Wannan yana buƙatar dumama firikwensin zuwa wasu yanayin zafi da gangan.
