What are the consequences of a lean air-fuel mixture?

[Madison]

It will reduce the combustion speed of the fuel. Part of the mixture's combustion will occur when the piston moves toward the bottom dead center. This portion of combustion not only converts less heat into mechanical work but also dissipates relatively more heat through the cylinder wall to the cooling water or radiator. Therefore, an excessively lean mixture can cause engine overheating, reduced power output, and may lead to irregular engine operation or failure to start. Here is an introduction to automotive air-fuel mixtures: An automotive air-fuel mixture refers to the combination of fuel and air, typically gasoline or diesel mixed with air. However, with advancements in automotive technology and fuel diversity, it now also includes mixtures with various combustible gases such as natural gas, methane, coal gas, as well as ethanol and methanol blends.