Is it normal to have oil in the throttle?

There is oil in the throttle, which is normal. Throttle oil is discharged into the air intake through exhaust gas recirculation of the engine. During engine operation, combustible mixture will enter the crankcase. In order to discharge excess exhaust gas, the engine has a component called exhaust valve, which is connected to the intake pipe, so that excess exhaust gas will enter the engine through the exhaust valve for re-combustion. After the car travels to a certain mileage, the throttle will have different degrees of dirt, usually at the throttle flap. Too dirty throttle will cause engine idling instability and jitter. General vehicles can be inspected and cleaned for 20,000 kilometers. As long as it's not particularly dirty, just ignore it. Don't agree to clean the throttle if you find a little oil stain.