You know the feeling: you are cruising nicely or stuck in traffic, then you see that small amber light light up on your dashboard. “Check Engine.” Two words that can change any ordinary commute into a minute of silent panic.
However, that light does not necessarily entail tragedy. Nevertheless, it should not be overlooked. The check engine light (CEL) is how your vehicle is telling you that something is not going well with the system. Although the issue may be a simple one at the moment, it may become a major repair should you not attend to it.
Fine, but what is the meaning of that light? We will discuss the most popular reasons it comes on.
A loose or faulty gas cap
A fuel system on your vehicle is closed to ensure that the fuel does not evaporate. In case the cap is not screwed on to the full extent or the seal is broken, it interferes with that system. The onboard computer (the ECM) will sense a leak of vapor and illuminate the CEL to draw your attention.
A bad gas cap may also lead to the loss of a mile or two of gas mileage. The solution is tightening or replacing the cap. In a few drives, the light usually switches off automatically.
Oxygen (O₂) sensor failure
The oxygen sensor checks the level of unburned oxygen in your exhaust. This information assists the ECM in manipulating the air-to-fuel ratio to achieve efficient combustion. When the O2 sensor is defective or dirty, the computer in your car cannot perform the correct adjustments. As a result, your car would be running poorly, consuming more fuel, and emitting more.
Short trips and stop-and-go driving due to traffic are common in cities. This makes sensors wear out more easily because of carbon accumulation. Replacing a faulty O2 sensor will avoid additional damage to the catalytic converter. Just find a trusted Auto Repair Shop Virginia Beach VA to accurately diagnose your car before further damage occurs.
Defective catalytic converter
The catalytic converter converts the dangerous exhaust gases (carbon monoxide, nitrogen oxides, hydrocarbons) to less dangerous ones. Once it begins to malfunction, your car will tend to lose power, smell of rotten eggs, and the check engine light will come on.
Catalytic converter problems generally build up over time. This can be due to unburned fuel in the case of misfires or a faulty O2 sensor. This is one of those issues that you should not disregard. Early detection can at times rescue the converter.
Defective spark plugs or ignition coils
The ignition coils and spark plugs ignite the air-fuel mixture in each cylinder. In case of failure, the consequence is incomplete combustion or a misfire.
Misfire manifests as shaking, rough idling, or slow acceleration. It is one of the most frequently occurring causes of a flashing (not steady) check engine light. When it is flashing CEL, the misfire is so intense that it may cause harm to your catalytic converter. Therefore, it is better to pull over and get it checked as early as possible.
Malfunctioning Mass Air Flow (MAF) sensor
The MAF sensor is used to determine the amount of air that moves into your engine and aids the computer in adjusting the mixture of the fuel. In case it is dirty or unhealthy, you will detect symptoms such as:
- Hard starts
- Slowness when accelerating
- Low fuel expenditure.
Frequent replacement of air filters can prevent MAF issues before they cause a check engine light.
Transmission or emission system errors
Modern cars are not only keeping track of the engine, but also the transmission and the emission systems. A check engine light can be explained by:
- A slipping transmission
- A defect of the shift solenoid
- A leak in the EVAP system.
They are more complicated problems and will often need to be diagnosed using scans. That’s why some repair shops, like the London Bridge Auto and Transmission Repair Shop Virginia Beach, use specialized tools to read trouble codes directly from the car’s computer. This traces them to the exact component or system that’s malfunctioning.
Sensor malfunctions or wiring malfunctions
The light does not always indicate that there is something wrong with the engine itself, and it is the sensors that are reporting false information. Modern automobiles are supported by dozens of sensors that are linked by complex wiring harnesses. Signals can be interrupted by corrosion, moisture, or rodent damage and cause the light to turn on.
You can avoid false alarms by periodically inspecting wiring and sensor connectors before they become actual headaches.
The takeaway
A solid check engine light is typically a non-urgent issue. But it needs to be inspected in the near future. A flashing light, however, indicates that the engine is misfiring actively and may bring severe damage if you continue driving.
Either way, the most appropriate thing to do is to have the system scanned. Look for a reliable auto repair shop. A professional mechanic can read diagnostic trouble codes (DTCs) and determine whether the repair is a minor or a major one.