What are the reasons for the Mazda 6's lack of acceleration without any fault codes?

[DeJace]

The reason for the Mazda 6's lack of acceleration is due to excessive carbon buildup in the throttle body, among other factors. Below are the specific reasons for the Mazda 6's lack of acceleration: Carbon buildup inside the engine: When there is excessive carbon buildup inside the engine, the gasoline sprayed by the cold start injector is largely absorbed by the carbon deposits, resulting in an overly lean air-fuel mixture during cold starts, making it difficult to start. Ignition system: Issues with the ignition system; check the working condition of the spark plugs, high-voltage wires, and ignition coils. Poor performance of the ignition system or improper spark plug firing can also lead to such symptoms. Check if the spark plugs have excessive carbon buildup and replace them if necessary. Unstable fuel pressure: Abnormal fuel pump supply pressure or incorrect readings and poor performance of the intake pressure sensor can cause vehicle shaking. Check the fuel pressure and replace components if necessary.