Causes of Lean Air-Fuel Mixture in Automobiles

[BethanyRose]

About the causes of lean air-fuel mixture in automobiles are introduced as follows: 1. Insufficient fuel injection. Various intake sensors fail to accurately detect the intake air volume, resulting in insufficient fuel injection; excessive carbon deposits adsorb the fuel injection; the closed-loop control of the oxygen sensor fails. 2. Low fuel pump pressure. In many cases, the lean air-fuel mixture is caused by low fuel pump pressure, and there are also reasons such as excessive clearance of the fuel pump rocker arm or too thick gasket between the fuel pump and the cylinder block that lead to a lean air-fuel mixture. 3. Effects of a lean air-fuel mixture. When the air-fuel mixture is too lean, the combustion speed of the fuel decreases, and part of the mixture combustion will occur when the piston moves toward the bottom dead center. Not only does the combustion of the lean mixture convert less heat into mechanical work, but the heat lost through the cylinder wall to the cooling water or radiator fins increases relatively.