A car that won’t start even though the battery is good can be confusing. The dashboard lights may turn on, the radio may work, the headlights may look bright, and a battery tester may even say the battery is healthy — but the engine still refuses to start.

This usually means the problem is somewhere else in the starting, fuel, ignition, security, or engine management system.

A car that shakes when accelerating is more than just annoying. In many cases, it is a warning sign that something is wrong with the engine, ignition system, drivetrain, tires, suspension, or transmission.

Sometimes the problem is simple, such as a tire imbalance or worn spark plugs. But in other cases, acceleration vibration can point to a serious issue like an engine misfire, bad CV axle, failing engine mount, or transmission shudder.