What are the symptoms of Audi's waste gas valve being broken?

What are the symptoms of Audi's waste gas valve being broken? What are the symptoms of Audi's waste gas valve being broken? In the morning, the cold car will have the problems of unstable idle speed and serious car jitter. These are all signs that the Audi waste gas valve is broken. The simplest way to judge the failure of Audi waste gas valve is: 1, start the tachometer, the speed is above 1000 rpm, and the idle speed is unstable. You can tell from the sound that the waste gas valve is broken. 2. If the waste gas valve is damaged, the dashboard will show that the engine fault light is on, but this situation will not affect the continued use. Replace the waste gas valve with a new one, and it can only return to normal after clearing the fault light. 3. Check whether the exhaust pipe emits blue smoke and whether the oil is easy to burn quickly. When accelerating or decelerating, you will feel jitter, and the engine idle speed is about 100 rpm higher than usual. ? @20 19