kylmäkäynnistyksellä

Kylmäkäynnistyksellä refers to the process of starting an internal combustion engine from a cold state, meaning the engine has not been run for a significant period and has cooled down to ambient temperature. This contrasts with a warm start, where the engine is still at its normal operating temperature. Cold starts present several challenges for an engine.

During a cold start, the engine oil is thicker and does not lubricate moving parts as effectively or as quickly as when warm. This can lead to increased wear during the initial moments of operation. Additionally, the fuel mixture required for ignition needs to be richer when the engine is cold to ensure proper combustion. Modern engines have sophisticated fuel injection systems and engine control units that automatically adjust the fuel-air ratio and ignition timing to compensate for cold conditions.

The exhaust system also plays a role. Catalytic converters, which reduce harmful emissions, are less efficient at cold temperatures and require a certain operating temperature to become effective. Therefore, emissions are typically higher during the initial period after a cold start. Repeated short trips that do not allow the engine and catalytic converter to reach their optimal operating temperature can lead to increased wear and higher overall emissions. Understanding the implications of cold starts is important for engine maintenance and efficient operation.