The work examines the trends of changes in the flow rate of test liquid through electromagnetic nozzles before cleaning them with ultrasound and after exposure to high-frequency sound waves. In this regard, dependence of the actual liquid flow rate on the pressure drop of the test liquid across a fully open jet nozzle was studied. The analysis of the data obtained as a result of the experiments was carried out using statistical functions and by employing "Data Analysis"package of the Microsoft Office Excel. The objects of the current study were electromagnetic injectors DENSO 23209-39145 and VAG 06A906031BT of gasoline engines with distributed fuel injection. The test was carried out on a device for cleaning and analyzing fuel injectors HP-6B with an ultrasonic bath "Ultrasonic Cleaner". The presence of contaminants in the nozzle holes was detected using a Levenhuk DTX 90 digital microscope. © 2025 Elsevier B.V., All rights reserved.