What happened to the fuel consumption after Elantra changed the valve?

In the past, the throttle valve was used for a long time, with carbon deposition and small opening. There is no carbon deposit when replacing it now.

The super fuel consumption of Hyundai Elantra may be due to the following reasons:

1, the piston and piston ring are damaged, resulting in engine oil burning, and the fuel cannot be fully burned to do work;

2. Novice drivers go on the road, don't lift the accelerator, and don't pay attention to variable-speed driving, which invisibly causes the fuel consumption index to rise;

3, machine aging, computer oil control system failure;

4. The oil tank and tubing are damaged, and there is yin oil phenomenon.