Why is the BMW engine shaking badly?
2 Answers
BMW engine shaking badly reasons are as follows: Engine misfire: Engine misfire mainly refers to one or more cylinders of the engine not working properly, usually manifested as: obvious intermittent exhaust gas flow from the car, severe shaking of the exhaust pipe, and noticeable engine vibration, sometimes accompanied by a sputtering sound. This is mostly related to ignition coil failure. Engine mount rubber aging or loosening: The engine mount rubber is the rubber block between the engine and the frame. Its function is to reduce the vibration and cushioning during engine operation and to fix the engine. Once these engine mount rubbers age or loosen, the engine vibration will become abnormally severe. After replacing the engine mount rubber, the effect will be significantly reduced.
I've been running a repair shop for over a decade, and when it comes to BMW engines shaking like a sieve, it's usually one of these issues. The most common culprit is worn-out spark plugs—when they act up, the car shakes along. Then there are the rubber cushions in the engine mounts, which tend to fail easily in BMWs. One of my recent customers had this exact problem—the car shook badly at idle but smoothed out while driving. If the shaking is worse during cold starts but improves after a few minutes, it might just be carbon buildup. If the dashboard warning light comes on along with the shaking, there's an 80% chance it's a faulty ignition coil or a clogged fuel injector. The worst-case scenario is a misfiring cylinder—you'll feel one side of the exhaust pipe hot and the other cold. Never ignore it—hook it up to a diagnostic scanner and read the trouble codes ASAP.
