It always happens unexpectedly, doesn’t it? You’re driving along minding your own business, and then all of a sudden your check engine light is on. Typically, there’s no reason to panic unless your car has stopped working. Instead, we recommend having your local mechanic take a peek and see what’s behind that check engine light. But if you can’t wait to hear the final diagnosis from your mechanic, we’ve got some unexpected reasons your check engine could be going on.
Check engine light cause by Loose or faulty gas cap
That’s right! It could be as simple as tightening your gas cap (we’ll keep our fingers crossed). Your gas cap and the valves in your gas tank keep your gas from escaping so that your engine can circulate your gas to keep your car running. If your gas cap is loose, you may lose fuel or your fuel system may not circulate your gas properly.
Faulty Catalytic Converter
Your catalytic converter changes carbon monoxide into carbon dioxide which helps protect the environment. When your catalytic converter fails or has an issue, it can lead to reduced fuel economy, reduced engine performance, and increased emissions. The fix is not always as easy as replacing it – typically a faulty catalytic converter can be caused by other issues, for example, a blown head gasket. Be sure to ask your mechanic to take a look to be sure.
Dirty or Faulty MAS Airflow Sensor & the Check engine Light
Your MAS airflow sensor determines how much fuel is needed to run your engine. It measures the amount of air entering the engine, and is typically susceptible to oil and dirt buildup. When this buildup is left unattended, your air to fuel ratio can get off – which can cause failures in other areas of the engine including lower engine performance, and decreased fuel efficiency.
Oxygen Sensor Failure
Your oxygen sensor measures the amount of unburnt oxygen in your car’s exhaust. The sensor will send data to your car’s computer which uses that information to regulate the mixture of air and fuel that enters the engine’s cylinders. If your sensor fails your car can keep running, but it will burn more fuel. If not repaired, this can damage your spark plugs and catalytic converter over time.
Your vacuum system helps decrease emissions by routing the fumes from evaporated gas through the engine. Your vacuum hoses can crack or dry out from intense cold during the winter or heat during the dog days of summer. As long as your mechanic is taking a look at your vacuum system, you’ll want to check for any cracked fittings or loose connections that can happen over time.
Your ignition coils deliver electrical pulses to each spark plug. When your engine’s computer sends a signal, the ignition coil releases pent up energy to the spark plugs. Ignition coils are prone to failure after several years, and the signs for failure include poor fuel efficiency, and decreased engine power.
Check engine light cause by the Fuel Injector
Each engine cylinder has a fuel injector, which is a small, electronically-activated valve that regulates how much fuel is sprayed into a cylinder during the intake cycle. Our fuel has impurities which combine with carbon created from the combustion process in the engine. This can cause the tiny holes on the fuel injector to clog. When fully clogged, your fuel injector can get stuck in the open position which then leaks fuel continuously into the cylinder.
Your engine typically runs between 195° – 220° F. The thermostat regulates the temperature of your engine and allows coolant to flow to the radiator when the engine heats up. When your engine thermostat is faulty, your car is not regulated which can cause your fuel to run improperly, and even overheat.
These unexpected reasons your check engine light turns on are not the only reasons. It’s best to have a local mechanic take a look under the hood and find out what’s really going on. If your check engine light is currently on, our team would love to help diagnose and repair your issue so you can get back to enjoying the roads this summer.