Posted on 8/29/2025
When your car is idling, it should run smoothly and steadily without shaking, sputtering, or vibrating excessively. A rough idle, where the engine feels unstable or inconsistent, is one of the first signs that something is wrong under the hood. While most drivers dismiss it as a minor inconvenience, it can point to problems that affect your engine’s performance, fuel efficiency, and long-term reliability. Ignoring it only allows the issue to worsen and can eventually lead to more expensive repairs. Common Causes of Rough Idle There are several potential reasons your vehicle might idle roughly, ranging from simple to complex. Clogged air filters, dirty spark plugs, or faulty ignition coils can all cause incomplete combustion, which results in a shaky idle. Fuel system issues, like dirty fuel injectors or low fuel pressure, can also cause inconsistent engine behavior. In some cases, vacuum leaks or carbon buildup in the intake manifold can disrupt the air-fuel ba ... read more