NGK gives tips for reviewing the ignition coil

Part must be checked along with the spark plugs every 10 thousand kilometers, annually or as directed by the assembler

São Paulo, November 2021 – Responsible for transforming the battery voltage – which usually varies between 12 and 14 volts – into high voltage, the ignition coil is a fundamental component of engine operation.. This is because the electrical current is conducted by the ignition cables or directly by the coils to the spark plugs and transformed into an electrical spark, which starts the burning reaction of the air/fuel mixture.

According to NGK - Japanese multinational manufacturer and specialist in candles, ignition coils and cables -, the high-tech component may have a shortened life due to lack of system maintenance. "Worn plugs are the main cause of coil failures, because they require more tension to generate the spark, which causes an overload in the entire ignition system, including coils and cables", explains Hiromori Mori, NGK do Brasil Technical Assistance consultant.

in old vehicles, the main ignition problem was generated by the carbonization of the spark plugs., that caused failures, starting difficulty and increased consumption. With the evolution of fuel injection systems, candles don't burn so easily. "Thus, the engine runs with worn out spark plugs, which raises the sparking voltage until the occurrence of damage to the coils. For this reason, It is important to carry out periodic maintenance of the ignition system", orient Mori.

The NGK specialist explains that the coils need to be checked in every spark plug revision, which must be carried out every 10 thousand kilometers, annually or as directed by the assembler to ensure the proper functioning of the engine. "Whenever you carry out the inspection of the candles, the driver must also check the condition of the cables and ignition coils to ensure that the entire system is working properly", emphasizes.

The review of the coils must be carried out in two steps. at first, a visual check is carried out to detect cracks and cracks in the body of the part and oxidation in the high voltage towers and terminals. In the second step, a measurement of the resistance of the coil's primary and secondary circuit is performed, of the supply voltage, supply current, command signal and response signal. "Coils that have an integrated ignition module do not perform the endurance test", points.

Another important factor to note is the engine's working temperature, since many coils are installed in it. "When the working temperature in the region of the coils is too high, there is a degradation of the electrical insulation resin of the coils, which can also cause damage to the part., therefore it is essential to observe the cooling system, responsible for engine cooling, identify if there is a lack of heat deflectors (metal sheets that have the function of heat deflection) and check for obstruction in the exhaust system", explains Hiromori Mori.