What is the normal idle speed of BMW 523?

What is the normal idle speed of BMW 523? About 700-1000; The engine idle throttle is too dirty or the fuel injector has too much carbon deposit, and the gear starts to shake, and the three-way catalytic temperature is not enough, so the engine carbon deposit seriously causes the vehicle to shake. Because the gasoline adsorbed on the carbon deposit after landing is sucked into the cylinder of the engine for combustion, the combustible mixture of the engine is sometimes rare and sometimes thick, resulting in idle jitter after cold start. Solution: The company cleans the oil circuit, and checks whether the idle motor has carbon deposit, so it should be cleaned.