Selection of Diagnostic Parameters When Assessing the Technical Condition of Spark Plugs

The study considers the problems of diagnosing the elements of the ignition system. It is necessary to choose diagnostic parameters providing small errors in the indirect measurement of the structural parameter during the evaluation process of technical state. It predetermines a small error in the method of measurement and an instrumental measurement error. The obtained diagnostic information on the availability of malfunctions is not always reliably and accurately. The study presents the results of testing of modern iridium spark plugs. The hypothesis is confirmed that the breakdown pressure of spark plugs affects the composition of exhaust gases. The relation between the breakdown pressure of spark plugs and the indicators of exhaust gases toxicity is established. It is determined that in the process of diagnosing the parameters of exhaust gases toxicity and breakdown pressure of spark plugs is possible to make a more accurate diagnosis about the condition of spark plugs. Based on the above statement, it is proved that timely replacement of spark plugs will increase their efficiency by 17%, will reduce the amount of exhaust gases emissions by up to 8%, and will also lead to engine fuel economy by 10–12%, which will lead to an increase of oil resource in the engine and, accordingly, the entire engine.