Rough Idle
Urgency: ModerateA rough idle means the engine RPMs fluctuate or the engine vibrates noticeably when at a standstill. This is often caused by ignition system problems, vacuum leaks, dirty fuel injectors, or a failing idle air control valve. The vehicle may feel like it's about to stall.
Need to read your codes?
An OBD-II scanner lets you read and clear diagnostic trouble codes from your vehicle's computer. Most scanners work with any car made after 1996.
Browse OBD-II Scanners on AmazonPossible Causes
- Worn spark plugs
- Vacuum leak
- Dirty fuel injectors
- Faulty idle air control valve
- Clogged air filter
- Bad ignition coil
Related OBD-II Codes
When to See a Mechanic
If the rough idle is accompanied by a check engine light or stalling, see a mechanic within a few days. Otherwise, schedule routine maintenance.
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