Kaltstarts

Kaltstarts refers to the process and challenges of starting an internal combustion engine or other mechanical systems under cold conditions. In automotive and industrial engineering, cold starts are distinguished from warm or hot starts by the presence of low ambient temperatures, thickened lubricants, and reduced fuel vaporization, which can impede reliable ignition and smooth operation.

Key factors influencing cold starts include battery condition and cranking speed, engine oil viscosity, fuel viscosity and volatility, and the condition of spark plugs, glow plugs, or grid heaters. In diesel engines, fuel can gel or wax at low temperatures, reducing flow; glow plugs or intake-air heaters raise cylinder temperature to aid ignition. Gasoline engines rely on fuel enrichment and cold-start strategies implemented by the engine control unit to improve starting.

Countermeasures include engine block heaters or coolant heaters, battery warmers, low-temperature oils, and improved fuel formulations. Electronic control systems adjust air–fuel ratio and ignition timing during startup; some vehicles employ grid heaters or intake-air heaters. In very cold climates, allowing a brief warm-up period or using preheating equipment reduces wear and emissions.

Kaltstarts is a topic in automotive engineering, maintenance guides, and cold-weather operation manuals, illustrating how temperature affects combustion, lubrication, and emissions, and how different propulsion systems address cold start performance.