Diagnosing a vibration can prove to be difficult, especially if the vehicle only vibrates under specific conditions, or, worse yet, the vehicle vibrates randomly. These vibrations are typically associated with the engine, and can be identified through connecting an computerized scanning tool, and monitoring the conditions in the engine as the vehicle vibrates. This will give a trained technician an understanding of why the vehicle is vibrating, to which they must apply classroom training and experience to identify the responsible component. If the engine and transmission are functioning properly, the engine and transmission mounts will be inspected, and failure will require replacement. If the vibration only occurs as the vehicle is moving, the technician will conduct a test drive and visual inspection of the vehicle. The suspension and driveline are inspected for worn or broken components, and in some situations, the wheels may be balanced and rotated.

Engine vibrations can come from a variety of sources, and repairs could range from a few minutes to many hours. Some vehicles are known for vibration issues that can arise from the slightest shift in a motor mount, and some have a reputation for the engine balance shaft failing. Both of these cause a fairly strong vibration, but the solution to one can be replacing the engine, and the solution for another is a small adjustment. In many cases the ignition system, engine and transmission mounts, and vacuum leaks are responsible for the vibrations, and servicing or replacing worn components typically restores the vehicle to proper operation.

Using a properly certified technician for diagnostic work can dramatically reduce diagnostics cost. The hourly rate may be higher, but the time spent in diagnostics will generally be much shorter. Also, a diagnosis from an ASE certified technician will be proven, and reached through testing, so they will not waste your hard-earned money replacing parts until the solution is stumbled upon. Lastly, many shops do not charge different diagnostic rates for all types of diagnostics. This results many times in a specific diagnosis being billed as general diagnostics.

Many spark plugs, engine mounts, and transmission mounts have been needlessly changed when a vibration is noticed in the vehicle. We only recommend changing these components if they are diagnosed as faulty, or if changing a component is a specified step required by a diagnostics platform.

Repairing a vibration will vary in difficulty and skill level. Vibrations caused by simple items, such as the idle air control valve or spark plugs, can be handled by most handy people. Technicians are required, however, when a diagnosis cannot be reached, when there is not enough information without professional scanning equipment, or when the repair is outside of the capabilities of the DIYer.