Can a Bad Alternator Cause Engine To Shake?

A bad alternator can cause an engine to shake. If the car doesn’t start or run properly, the problem may be with the alternator. A defective alternator can result in poor engine performance, including shaking.

There are several things that can cause a car’s engine to shake. One of them is spark plugs misfiring.

A spark plug is a piece of metal that conducts electricity from your car’s ignition system to the combustion chamber in order to ignite fuel and start the engine.

The reason why your engine is shaking is because the spark plug is not working properly and sending the right amount of electricity to the engine’s pistons. This causes them to move too quickly or too slowly, which can cause your engine to shake.

What other causes might be causing your engine to shake?

Engine shaking is a common problem that can be caused by a variety of factors. A bad alternator is one of the most common causes, but it’s not the only one. Engine shaking can also be caused by a loose belt or problems with your fuel system.

If you notice that your engine is shaking, take your car to an auto repair shop for an inspection. The mechanic will check for any loose belts and other issues that might be causing the engine to shake.

If they do find a loose belt or other problem, they will fix it for you and then drive your car to see if the shaking has stopped. If there isn’t anything wrong with your car, then it’s likely that a bad alternator is causing the issue.

Signs you have a bad alternator

When an alternator isn’t working correctly, it will usually cause one or more symptoms:

  1. Your battery won’t charge properly
  2. Your headlights dim when you turn on the A/C or other electrical accessories
  3. You notice that the lights on your dashboard are dimming when you try to start the car
  4. You hear a loud humming noise coming from under the hood when you start up your car

What Causes an Alternator to Fail?

The alternator is an important part of your car’s engine. It converts mechanical energy into electrical energy and sends it to the battery, which stores it for later use.

If you’re driving and all of a sudden your car starts shaking, it could be because of a problem with your alternator. This can happen for any number of reasons, including:

  1. The alternator belt has broken
  2. The alternator pulley is loose
  3. There’s too much friction between the brushes and commutator
  4. You have a bad bearing in the rotor assembly


Misfiring spark plugs and other engine problems can be caused by a bad alternator. If your car is shaking, stalling, or otherwise not running properly, it’s possible that the alternator is to blame.

Steven Hatman
Steven Hatman

We break down every information into easy-to-understand articles that cover all the categories anyone who owns a car needs to know about, such as oil , brakes , tires and etc. Our car guide is free and updated regularly for you to use as a resource, not only when you have an issue with your car but even before buying a new or used car! We also give tips on what to look for in each category or part of your vehicle.