The idle speed of lexus ES240 hot car is abnormal, and it doesn't ring at 1000. What happened?

It may be that the car was cold at first, and when the inner and outer rotors scraped, there would be abnormal noise when it was cold, and it would be much lighter when it was hot. As for why this happens, the main reason is that the protective oil film is poor when the car is cold, but it will be much better at high temperature. In this case, the oil pump needs to be replaced directly, and there is no sound after it is added to 1000 rpm, indicating that the hot car is over. There are many reasons for idling instability and jitter, especially when the cold car just started, which is often caused by too much carbon deposition on the throttle. This needs cleaning and matching! Ignition system and oil circuit failure, valve train wear, EGR valve stuck, abnormal sensor signal, poor line contact, etc. It will cause unstable idle speed, so it is better to find a professional to check it!