Why does my engine shake at idle?
A rough idle is the engine running unevenly while stopped.
Most likely causes
- Worn spark plugs or coils. Causes misfires.
- Vacuum leak. Often with a hissing sound.
- Dirty throttle body or air sensor. Common on higher-mileage cars.
- Worn engine mounts. Makes normal vibration feel worse.
Simple things to check
- Check if the check engine light is on
- Listen for hissing near the engine
When to stop driving
If the check engine light flashes, avoid driving until it's fixed.
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