5 Common Reasons Your Check Engine Light Is On

When the check engine light looms, it's easy to get worried about the cause. Every mile you drive turns into a guessing game. Left unresolved, the damage could compound along with the auto repair price.

Keep reading to discover five common reasons your check engine light is on.

1. The Gas Cap

Your car's gas cap seals in gas fumes and helps maintain the pressure in the tank. A missing or faulty cap leads to excess fuel loss and improper function of the tank.

Gas caps range in price from $15 to $25 depending on your vehicle. You can pick up a universal cap from your local auto parts store.

2. The Fuel Injector

If your fuel injector needs maintenance, this could be the culprit for the check engine light. Stalling out, high emissions, and bad acceleration are signs that your fuel injector needs cleaning.

Quick maintenance usually involves running a cleaning solution through the system. For pronounced clogs, the fuel injectors need to be removed. This happens as fuel deposits build up over time.

The fuel filter, pump, and injector are three essential parts of a system that moves gas through your car's system. If any of them malfunction, it puts more pressure on the other parts, leading to a breakdown. Get your fuel system cleaned on a yearly basis or as often as your car manufacturer suggests. 

3. The Throttle Body Assembly

The throttle body controls how much air enters the engine. When the throttle body malfunctions, your engine will run roughly while idling or while driving. A rough engine while driving is usually an indicator that the problem has gotten worse.

The throttle body should be cleaned periodically. The average price of cleaning or replacing this is $578. An experienced DIYer can clean and replace the assembly fairly easily. However, balanced airflow in the engine is essential to its proper function. Seek professional auto repair services if you don't feel confident making the correct repairs.

4. The Airflow Sensor

The Mass Airflow Sensor (MAF) works with the throttle assembly to determine how much fuel your engine needs to run. Symptoms of a MAF malfunction include stalling and low gas mileage. Untreated, this condition leads to malfunction of other parts of the engine system. This includes damage to the oxygen sensor, catalytic converter, and spark plugs.

5. The Spark Plugs

Changing spark plugs is a classic issue. This is because older cars needed to have them replaced every 25,000 miles. These days, spark plugs typically last over 100,000 miles. This is a fairly easy repair to do yourself if you know what you're doing.

When replacing spark plugs, replace all of them at the same time to avoid frequent repairs.

A yearly checkup will keep your car free of the most common ailments. Self-diagnosing can lead to a lot of unnecessary repairs. This guessing game could damage your engine more and become very expensive to fix. Contact your local repair shop to get an accurate diagnosis.