tändningsställ

A tändningsställ, often translated as ignition timing, refers to the precise moment during the engine cycle when the spark plug ignites the fuel-air mixture in the combustion chamber. This timing is critical for optimal engine performance, fuel efficiency, and emissions control.

In internal combustion engines, the ignition timing is usually expressed in degrees of crankshaft rotation before or after the piston reaches top dead center (TDC) on its compression stroke. Advancing the timing means igniting the mixture earlier, while retarding the timing means igniting it later.

The ideal ignition timing varies depending on several factors, including engine speed (RPM), engine load, fuel quality, and temperature. Modern engines use electronic control units (ECUs) to dynamically adjust the ignition timing in real-time, ensuring it remains within the optimal range under all operating conditions. This dynamic adjustment is often referred to as electronic ignition timing or spark timing control.

Incorrect ignition timing can lead to a variety of problems. Too much advance can cause engine knocking or pinging, a damaging phenomenon where the fuel ignites prematurely and unevenly, potentially leading to mechanical failure. Too much retard can result in a loss of power, increased fuel consumption, and higher exhaust gas temperatures, which can damage exhaust components.