<div>Internal combustion engines are prone to get carbon deposits or residue which accumulate due to incomplete fuel combustion. This can have adverse effects on engine efficiency and performance. Engine decarbonization is one of the recent technologies in automobile maintenance, which involves the removal of carbon deposits or residue from various components within the internal combustion engine, including valves, pistons, cylinder heads, and combustion chambers. Decarbonization methods typically utilize specialized cleaning agents or additives to dissolve and eliminate these carbon deposits claiming to enhance engine performance and restoring optimal functionality. This article focuses to study the effects of engine decarbonization on noise and vibration of an IC engine. Oxyhydrogen (HHO) carbon cleaning machine has been used for decarbonization of the engine. This research addresses a contemporary concern in automotive maintenance by investigating the potential benefits of decarbonization in reducing noise and vibration levels. The results obtained from the data analysis provide insights into the effectiveness of the HHO carbon cleaning in improving engine performance. After decarbonization, the average noise levels have been observed to be decreased by an average of 3.28%, with a maximum reduction of 8.42% at a specific location and RPM value. Additionally, the vibration levels decreased by an average of 3.44%, with a maximum reduction of 16.38% at a particular location and RPM value.</div>