La línea del check engine light is the most misunderstood warning in your car. It is not a death sentence – but ignoring it is. Here are the five most common causes, from cheap to serious.
The five usual suspects
1. Loose or bad gas cap. A loose cap lets fuel vapor escape and trips the light. Tighten it and the light often clears on its own.
2. Oxygen sensor. This sensor watches your exhaust. When it fails, your fuel economy drops and the light comes on.
3. Spark plugs or ignition coils. Misfires from worn plugs are a top cause, and they are cheap to fix if caught early.
4. Catalytic converter. Usually the most expensive item on the list, and usually a symptom of an ignored problem upstream.
5. Mass airflow sensor. Dirt and oil foul this sensor and make the engine run lean or rich.
When it is serious
If the light is flashing, pull over – that is a misfire that can damage the catalytic converter. If it is steady, get it scanned this week, not next month.
We come to you in Phoenix, read the codes, and tell you exactly what is wrong before any work. Text (602) 806-9444 to book a mobile diagnostic.