What are the reasons for high fuel consumption in manual transmission cars?

[Bennett]

Manual transmission cars have high fuel consumption due to obstructed air intake in the air filter. Clean or replace the air filter. The throttle valve is not closing properly; clean the throttle valve. Insufficient tire pressure. Engine oil is not filled according to the specified grade. Spark plugs have been used for too long, leading to decreased ignition energy. Engine coolant temperature is too high. Frequent braking, among other reasons. Below is related content: 1. Manual transmission cars: Cars that use a manual shift mechanical transmission to regulate speed. That is, the gear shift lever must be manually moved to change the gear meshing position inside the transmission, altering the gear ratio to achieve speed change. The gear shift lever can only be moved when the clutch is depressed. 2. Fuel consumption: Constant speed fuel consumption is the vehicle's fuel consumption per 100 kilometers obtained in the constant speed fuel consumption test specified by national standards for certain types of vehicles.