While there are many lights in your car’s instrument cluster but the one that stands out most is the check engine light. It's possible to go for hours without ever seeing one of these lights, but there are steps that you can follow when you do.

The problem with the check engine light is that it may come on for a range of reasons. The check engine light is there to let you know that something is wrong, but other than the fact that it flashes, you won't get much more details. If you ignore it, you may put your vehicle and even your life in danger.

But, it doesn't indicate that the issue is urgent. You can check for anything from a loose gas cap to something more serious.

What do check engine light colours or actions refer to?

The check engine light could not always appear the same color. The check engine light can be red, orange or yellow, or even both. A red light on certain vehicles may indicate a significant issue that needs to be resolved immediately. A blinking light can also be displayed on other vehicles to indicate the same issue. The yellow or orange lights are not as serious, but you should still get it checked to find out what caused it.

What is the reason that causes the check engine light to turn on?

The most common reason your light turns on is due to a loose fuel cap. This usually happens immediately after filling up at a fuel station. It's easiest to check the cap first. It does not require any assistance from a technical expert. It's straightforward to change a cap if it is defective.

The light could also be caused by certain components that are located under the under the hood. Here are some typical warning signs that you should be aware of

1. Oxygen sensor (or O2 sensor)

The oxygen sensor measures the amount of fuel burned by the car. There are usually between two and four oxygen sensors found in the majority of automobiles. If one is damaged the engine light might be activated. A faulty sensor will reduce fuel efficiency and emissions, but left unchecked it may cause damage to the catalytic converter. This is a costly fix that will cost at least $1,200. Swapping out the oxygen sensor is far cheaper and comes at a price of $260 and could be something you are able to perform yourself.

2. Catalytic converter failure

The catalytic converter is a key component of the car's exhaust system. It converts carbon monoxide produced by the engine to carbon dioxide via the exhaust system. While it's not difficult to fix to fix, it's costly to repair. Regular oil changes help to ensure that it is working correctly. Other components could also be affecting the operation of your converter, such as an oxygen sensor that isn't working or sparkplugs.

3. Failure of the ignition coil or spark plug

Ignition coils generate spark plugs with the power they need to ignite the engine's cylinders If there's any misfire in that process, it might be enough to turn the engine light on. Diesel engines do not come with spark coils or spark plugs. This issue is only for vehicles powered by gasoline.

If spark plugs wear out, you may notice that your car has a slow acceleration. Incorrect ignition coils may cause similar problems, so if you believe it's spark plugs, it may be the ignition coil.

4. Airflow sensor fails

The car's mass flow sensor monitors how much air is getting into the engine. It also determines the amount of fuel it should inject. It could cause increased emissions, or even cause stalling, if it fails.

Air filters are one of the most frequent causes. Blockages in the filter can result in sensor failure in the event that they are not replaced or installed correctly. Airflow sensors for mass circulation are expensive replacements, costing around $400. However you can stop the issue from occurring by regularly replacing the filter.

5. Replace the thermostat

The thermostat works like any regular home version, but with the exception that it controls the flow of coolant through the engine. If the coolant has become dirty or contaminated by dirt or other substance, it could be corrosive, resulting in overheating of the engine.

While not exactly the same an oil leak can also trigger the light once the engine heats up to a high temperature. Since you've parked your vehicle for a longer duration, it's much easier to detect a leak.

6. Replace exhaust gas Recirculation (EGR) valve and clean the entire EGR ports

EGR, also known as exhaust gas recirculation or EGR valve, keeps the nitrogen oxide levels in your engine lower by redirecting exhaust gas back into the combustion chambers for cooling. Most modern cars have an electrically-controlled valve that opens and closes from the onboard computer. The engine light can be turned on if the flow is not the correct.

Carbon can build up and adhere to the system clogging it. It is possible to spot it when you look under the hood, but an indication is you feel or hear an 'hiccup' or stall during idle. It's possible to clean out the valve, but it's not accessible in all vehicles. If the buildup is high replacement of the valve and a new gasket can cost about $500, based on the components and labor.