Ignition system — general description (Audi A4 B5)

The ignition system, sending a spark in a timely and targeted manner, ensures the correct combustion process of the fuel-air mixture in the engine. And this happens instantly, because at 3000 revolutions, each engine cylinder requires 25 sparks per second. At 100 sparks per second in a four-cylinder engine, this is 6000 sparks per minute, 360,000 per hour, etc.

In order for the spark from the spark plug to get into the combustion chamber at all, there must be a voltage of 30,000 V between the spark plug electrodes. But the battery only supplies 12 V. This means that the battery voltage must be significantly transformed. Then, when transmitting the spark, we are not talking about tenths or hundredths of a second, but about thousandths. A little faster or a little slower and defects in ignition and engine power appear.

(Material republished from the website: AudiManual.ru)