<![CDATA[This study aims to analyze the effect of using deposit cleaner liquid on exhaust emissions of gasoline engine vehicles using a gas analyzer. The object of the study was the Daihatsu Terios 2019 A/T with test parameters in the form of carbon monoxide (CO), hydrocarbons (HC), and carbon dioxide (CO2) at engine speed variations of 1000 RPM, 2000 RPM, and 3000 RPM. Therefore, this study uses an experimental method by comparing the results of exhaust emissions before and after the use of a deposit cleaner. The test was carried out for 1 minute at each engine speed variation using a gas analyzer. The results showed that the use of Deposit Cleaner was able to reduce CO levels at all engine speed variations, namely from 0.05 % to 0.02 % at 1000 rpm, from 0.06 % to 0.03 % at 2000 rpm, and from 0.06 % to 0.02 % at 3000 rpm, with an average reduction of 58.89%. HC levels also decreased from 13 ppm to 4 ppm at 1000 rpm, from 12 ppm to 6 ppm at 2000 rpm, and from 11 ppm to 5 ppm at 3000 rpm, with an average decrease of 57.93 %. Meanwhile, CO₂ levels only experienced a small change from the range of 13.7–13.8 % to 13.4–13.6 %, thus not showing a significant change. Based on the results of the study, it can be concluded that the use of Deposit Cleaner effectively improves the quality of engine combustion, as indicated by a consistent decrease in CO and HC emissions across all engine speed variations. Thus, Deposit Cleaner has the potential to be an alternative fuel system maintenance that can increase combustion efficiency while reducing exhaust emissions in motor vehicles.]]>
