Generally, the car throttle valve is cleaned every 20,000~30,000 kilometers.
If there is no idling instability, engine shake, significant increase in fuel consumption, acceleration and weakness, etc. It is best to clean it. Carbon deposition is a process of slow accumulation, and it will not directly cause serious malfunctions. Therefore, it is necessary to pay attention to the condition of the vehicle and solve the problems in time.
Is your throttle body acting up?
When your throttle body isn’t working properly, some red flag symptoms would be an extra-high idle, or an extra-low idle. With a low idle, you might even notice your vehicle stalling out at red lights. Low idle speed typically is the result of throttle blade coking, restricting airflow, and essentially snuffing out the combustion inside your engine).
Unusually high, or inconsistent revs at an idle could be the result of too much air passing through the throttle body – likely the result of a vacuum leak. (New paragraph)
Either of these issues would drastically affect your engine performance, and most likely your Check Engine Light would turn on with a P2119 code, as well as, with the vacuum leak condition, P0171 & P0174 lean codes would also appear.
In modern vehicles, most issues with the throttle body will likely be electrical in nature. It’s important not to move the valve on your throttle body manually. Some car owners may do this in an attempt to clean the valve, but it may confuse your vehicle’s computer as to the resting position of your valve.