How to fix check engine light.

Sometimes a check engine light symbol will illuminate on the dashboard of a person’s car and it won’t turn off so since it doesn’t tell you anything more people are left wondering what made it come on. Well, basically it’s telling you something’s wrong with the emission system which it monitors, so take a closer look at the most common reasons why your check engine light comes on.

Why your check engine light comes on.

Keep in mind that steady light means it’s something minor and a blinking light means it’s something more serious, one big caveat. A lot of these parts do eventually need to be replaced because they just get old, tired, worn-out, however some of these items will wear off prematurely because of not performing routine maintenance:

1. Faulty Gas Cap

Gas Cap maintains pressure in the fuel tank and keeps fumes from being released into the air. The gas cap could simply be loose, damaged or missing.

2. Faulty oxygen sensor

Oxygen sensor measures the amount of unburned oxygen in your exhaust system and controls the air fuel mixture going to the engine. Your vehicle can have more than just one of these premature failure. It can be caused due to your engine burning more oil than normal or also higher concentrations of ethanol in your gasoline. Not replacing will cause reduced gas mileage rough and eventually damaging spark plugs
and catalytic converters.Gas Cap maintains pressure in the fuel tank and keeps fumes from being released into the air. The gas cap could simply be loose, damaged or missing.

3. Faulty air fuel ratio sensor

Air fuel ratio sensor measures the air fuel mixture in the exhaust manifold and controls the air fuel mixture going to the engine. Failure of this part will cause reduced gas mileage a drop in engine power output and delayed response when accelerating as well as rough idling and even stalling.

4. Faulty mass airflow sensor

Mass airflow sensor measures how much air is coming into the engine and then determines how much fuel to send to the engine. Failure of this part can cause a reduction in gas mileage, engine hesitation during acceleration, harm oxygen sensors, spark plugs and catalytic converters.

5. Faulty ignition coils

Ignition coil sends electrical current to the spark plug. Premature failure of this part can be caused by driving in extremely high temperatures; extremely wet weather or even driving through a puddle. Failure of this part can cause engine misfiring, rough idle or reduction of power and not being able to start the engine.

6. Faulty spark plug wires

Spark plug wires sends electrical current from the ignition coil to the spark plug. Orange spark plug wires will cause reduced gas mileage loss of power and acceleration and in severe cases engine misfiring and stalling. It can also cause damage to oxygen sensors, air fuel ratio sensors, ignition coils and catalytic converters.

7. Faulty spark plugs

Spark plugs allows the air fuel mixture to ignite causing engine combustion. Worn spark plugs will cause reduce gas mileage loss of power, engine misfiring and difficulty starting. It can also cause damage to oxygen sensors, air fuel ratio sensors, ignition coils and catalytic converters.

8. Faulty thermostat

Thermostat regulates the engines temperature. A bad water pump, worn or loose water pump belt or something as simple as a low radiator coolant level could prevent the thermostat from operating properly. Premature failure can be caused by not changing the radiator coolant. Failure of thermostat will cause a high temperature gauge reading and engine overheating.

9. Faulty EGR valve

EGR valve sends a portion of the exhaust gasses back to the combustion chamber of the engine to reduce emissions. Premature failure of EGR valve can be caused by not changing your engine oil regularly which causes carbon buildup and clogs the valve. The good news is it can often be fixed just by cleaning it. A faulty EGR valve will result in reduced gas mileage, higher emissions, rough idling, engine hesitation, reduced overall power. It can even cause serious engine damage.

10. Faulty evaporative emission canister purge valve (EVAP)

This part prevents fuel vapor in the fuel tank from being released into the atmosphere and controls the amount of fuel vapor released from the charcoal canister. A faulty valve usually means it’s stuck open or the vacuum hoses attached to it or damaged which can cause rough idling and hard starting.

11. Faulty catalytic converter

Catalytic converter helps turn harmful carbon monoxide into carbon dioxide. Failure of this part is due to other underlying problems that have not been fixed. The most common being faulty oxygen sensors, mass airflow sensors, spark plugs or spark plug wires. Of all the items we’ve covered this will be the most expensive to repair. If you don’t replace it your vehicle will have reduced overall engine performance to include reduce gas mileage, reduced acceleration and power and may run at higher temperatures. It also won’t pass emission tests.  

If your check engine light does come on the easiest way to determine which part needs to be replaced is to go to an auto parts store and most of them will diagnose the problem for free with a handheld computer. They can plug into your car which only takes a couple of minutes. Most of these parts aren’t that difficult to replace and you might be able to do the work yourself. If you can’t do the work yourself then you’ll need to take it to a mechanic so.

I hope this helps somebody out there.