You feel the engine shimmy and shake when the car is sitting at an idle. You feel the engine shiver when you accelerate. You notice jarring when are going down a hill. There are all kinds of situations when you may feel a car engine shudder, and in every instance, it is a bothersome experience. A shuddering engine can point to serious problems, but the cause of the shuddering is not always a serious issue. As the owner of a vehicle, it's always best to know a little about what's going on either way. Here's a look at some of the common causes of a shuddering engine. 

Disconnected Vacuum Lines

Beneath the hood, most engines have a series of vacuum lines and hoses that are there to regulate pressure to various engine components. If just one of these lines slips out of place, it can definitely cause the engine to shake. Grab a flashlight and take a look at the different hoses under the hood to make sure you don't see a free hose that has dismounted from its place.

Broken Motor Mounts

The engine and all its components are held steadily in place by a series of heavy-duty mounts that attach to the frame of the vehicle. If one of the motor mounts breaks, whether it is on the side, bottom, or top of the motor, the usual stability will be gone, and your engine will be a lot more shaky than usual. You may notice shaking especially when the transmission shifts from one gear to the next, but the engine will be much less stable in general. 

Timing Belt/Chain Problems

The timing belt or timing chain of the motor keeps the pistons firing in a uniform and recurrent fashion. If the engine is out of time because the timing belt or timing chain is off, it can cause all kinds of problems, even engine shuddering. The telltale sign that the timing chain or belt is off is the engine not idling smoothly, so it will probably die quite often. However, even when you are able to keep the engine running, you will also notice shuddering and shaking.

A shuddering engine is not an issue that you should just let slide. If you have issues with an engine that shakes and shimmies, reach out to an auto mechanic like First Class Engines for advice about the parts you need to make repairs.