After cleaning the throttle and nozzle, the noise is loud and the car is off center. What's the matter?

In general, cars don't need to clean the nozzle. Fuel nozzle is a high-precision thing, and improper operation will cause damage. And as long as the carbon deposition at the air inlet is not serious, it does not need to be cleaned. Just clean the throttle at most. The throttle is like the carburetor of the original car. There is a certain amount of carbon deposit in a certain period of time, which needs to be cleaned up, otherwise there will be idle instability or idle jitter. I suggest you go to an experienced garage and check the car fault code with a computer to see if there is a fault code in the fuel injection circuit.