BMW X3 shaking after cold start and while idling, dealer claims it's normal on BMW X3

Some BMW X3 owners report experiencing significant shaking after a cold start and while idling, which can be concerning, especially when dealers claim it's normal. This shaking is often noticeable, with vibrations felt in the driver's seat until the engine stabilizes as oil circulates. Some owners find that the car vibrates significantly until they touch the gas or start driving, at which point it becomes smooth. Additionally, the appearance of code "P050b" after cold start shaking may indicate engine misfires or other mechanical issues that require attention. This cold start shake can sometimes be linked to dirty Vanos solenoids due to overused engine oil and infrequent oil changes, with cleaning potentially alleviating the issue. Owners are also advised to check spark plugs for wet or black residue, which could suggest a leaking or defective injector contributing to the shaking. If excessive shaking persists, it may be wise for owners to investigate these potential causes to ensure optimal vehicle performance.