Vehicle Health Index (VHI)
Since 2011, the CarMD® Vehicle Health Index™ has revealed the most common check engine issues, repairs, costs, regional trends, and reliability rankings by make and model.
Browse ReportsCheck Engine Light Insight
The check engine light comes on when a vehicle’s computer detects a problem that affects emissions or drivetrain issues. Don’t panic when the check engine light comes on, but get it diagnosed ASAP. It can be as simple as a loose gas cap.
But a flashing check engine light can indicate a more serious problem such as an engine misfire that needs immediate attention from roadside assistance.
If your car’s check engine light is on, it will not pass its state emissions test and negatively impact fuel economy if ignored.
Vehicle Health Index (VHI)
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