Mercedes-Benz coupe c260 started without stepping on the accelerator, and the speed reached more than 1000 rpm.

Sudden speed increase without stepping on the throttle may be due to a problem with the throttle or a problem with the sensor near the throttle.

When the owner steps on the accelerator, he does not directly control the fuel injection quantity, but controls the throttle opening. When the throttle opening becomes larger, the air entering the engine will also increase, and the ECU will also command the fuel injection system to increase the fuel injection quantity. In fact, the sudden increase in speed will happen in every car. Auto start's high speed is called high idle state, and its essence is idle speed, which is controlled by on-board computer. When the engine is started under different conditions, the speed will change obviously. For example, in winter, the temperature difference between the starting state and the normal operation of the engine will be great, so the initial starting speed of the engine will increase accordingly. The throttle is the throat of the engine. When we step on the accelerator pedal, we actually control the opening of the accelerator, not directly control the fuel injection. When the throttle opening becomes larger, the air entering the engine will increase, and ECU will command the fuel injection system to inject more fuel. On the intake system of the engine, there is an air flow sensor, which can detect the air flow and feed back the signal to the ECU.