What should I do if Jetta's idle speed is high?

It is normal for Jetta to have a high idle speed.

Because the weather is cold now and the viscosity of engine oil is high, changing antifreeze engine oil can't reach the hot state. There is nothing to adjust.

In addition, don't add too much throttle when starting, because the oil will reach the bottom of the chassis when the car is stationary, and the oil pump won't get up when starting. At this time, increasing the throttle will cause serious wear and tear to all parts.