What are the reasons for oil entering the throttle body?

[AmaraMarie]

The reason for oil entering the throttle body is: The engine's exhaust gas recirculation is discharged into the intake manifold, which over time forms deposits on the throttle body, and this is a normal phenomenon. The effects of a damaged throttle body are: 1. Unstable engine idle, persistently high idle speed that does not drop, and difficulty in starting the engine, especially during cold starts; 2. The engine has no idle speed; 3. Insufficient engine power, poor acceleration performance, and unstable operation; 4. The car's exhaust pipe emits black smoke, and fuel consumption increases. The reasons for a dirty throttle body are: 1. Driving environment, poor filtration by the air filter, and high levels of dust in the surrounding environment; 2. Poor quality engine oil with high evaporation rate; 3. Oil vapor and impurities are produced in the crankcase; 4. The throttle body sucks in dust after the engine is shut off.