As you hit the road with a fresh oil change, the hope of improved engine performance fills the air. But sometimes, that hope is shattered by the sudden appearance of the check engine light.
What could this unexpected illumination mean?
While these two events might seem unrelated on the surface, there is indeed a connection that can trigger the check engine light after an oil change.
This Article Contains:
- What Is the Check Engine Light
- Why Is the Check Engine Light On After an Oil Change? (Causes + Fixes)
- Other Possible Causes of the Check Engine Light
- How to Reset the Check Engine Light
What Is the Check Engine Light
The check engine light is an alert that illuminates when your car’s onboard computer detects a potential issue. It serves as an indicator for drivers to address various problems and prevent further damage.
Usually, the check engine light comes on briefly after an oil change, as the oil requires a few minutes to circulate through your engine and build oil pressure. After the oil sensor recognizes the pressure, it goes off.
However, there are cases when it doesn’t turn off. Let’s explore why.
Why Is the Check Engine Light On After an Oil Change? (Causes + Fixes)
An oil change is a straightforward procedure, but mistakes can happen. These mistakes can affect your vehicle, illuminating the check engine light.
Here are common reasons why the check engine light might come on after an oil change:
1. Low Oil Level
Performing an oil change with the wrong quantities of engine oil can lead to a low oil level.
If the engine oil level is below the recommended mark, it can lead to inadequate lubrication. This inadequacy can cause an engine misfire, illuminating the check engine light and the oil change light.
How to fix: Check your owner’s manual for the recommended amount of oil your vehicle needs before every refill. The engine oil should be between the high and low markings on the oil dipstick.
2. Using the Wrong Oil
How to fix: Drain your engine oil and refill it with the correct oil type. You can determine which oil type your vehicle needs by checking the top of the oil filler cap or your owner’s manual.
3. Low Oil Pressure
Oil pressure is crucial for maintaining proper lubrication within the engine. Low oil pressure can result from various issues, such as a faulty oil pressure sensor, an oil leak, or a damaged oil pump.
The engine may not receive proper lubrication if the oil pressure is low. This lack of pressure triggers the oil change light and the check engine warning light. It can also lead to engine damage if ignored.
How to fix: Regularly checking the oil pressure sensor, oil filter, or oil pump can help prevent low oil pressure conditions. Fixing a detected oil leak can also be helpful.
4. Excess Oil
Just as having too little motor oil is a concern, having too much motor oil can also pose problems. Excess oil can lead to foaming, reduced oil circulation, and increased engine pressure. This increased pressure can trigger the check engine light and lead to an engine misfire.
How to fix: Remove the excess oil with a suction oil pump.
5. Oil Dipstick Not Fully Seated
The oil dipstick measures the oil level in your car’s engine. After an oil change, the oil dipstick may not be adequately seated due to repeated removal. This mishap allows unmetered air to sneak into the engine. The unmetered air can cause inaccurate computer readings, triggering the check engine warning light.
How to fix: Open your hood, locate the oil dipstick, and push it in entirely.
6. Missing Oil Fill Cap
The oil cap is a removable cap that covers the oil tank. It provides access to check the engine oil level.
A missing oil filler cap can disrupt the engine’s emission control system as unmeasured air enters the system, causing imbalances. The illuminated check engine light will alert you of this potential issue.
How to fix: Double-check the tightness and presence of the oil cap.
7. Oil Filter Is Not Properly Seated
During an oil change, the oil filter is replaced to ensure clean engine oil flows through the system, free of debris and contaminants. If the new oil filter isn’t seated correctly or the old gasket isn’t removed, it can lead to an oil leak and reduced oil pressure, prompting the oil light to illuminate.
How to fix: Ensure you use a manufacturer-recommended oil filter and that it’s properly tightened.
While the above factors contribute to the check engine light illuminating after an oil change, there are possible alternative reasons why your check engine light activates.
Other Possible Causes of the Check Engine Light
Besides an oil change, various factors can trigger this dashboard light. Understanding the causes can provide valuable insight into how to clear the check engine light.
Here are some other check engine light triggers:
1. Faulty Oxygen Sensor
The oxygen sensor measures the oxygen content for efficient fuel combustion. However, inaccurate data from a faulty sensor can lead to a misfire, causing the onboard computer to trigger the check engine light. For accurate readings, you should replace an oxygen sensor every 60,000 to 90,000 miles.
2. Damaged Catalytic Converter
The catalytic converter converts harmful pollutants in the exhaust gases into less harmful substances. A damaged catalytic converter can increase emissions, triggering the check engine light. The catalytic converter is quite sturdy and must only be replaced every 10 years unless there’s a severe issue.
3. Faulty Ignition Coil
An ignition coil converts the voltage from your vehicle’s battery into the spark necessary to start your engine. A faulty ignition coil can lead to an engine misfire, illuminating the check engine light. We recommend an ignition coil replacement every 80,000 to 100,000 miles.
4. Damaged Spark Plug
A spark plug ignites the air-fuel mixture in the combustion chamber. Once the spark plug becomes worn or damaged, it can lead to rough idling or misfires and trigger the check engine light. Generally, a spark plug will last anywhere from 30,000 to 50,000 miles.
5. Loose Gas Cap
The gas cap prevents gas vapors from escaping and debris from entering the fuel system. A loose gas cap can illuminate the check engine light as it disrupts the vehicle’s fuel system. You should replace the gas cap if it’s cracked or broken or get a new one every 50,000 miles to avoid issues.
6. Clogged Air Filter
The air filter ensures clean air reaches the engine for combustion. A clogged air filter restricts airflow, illuminating the check engine light. We recommend you replace your air filter at least every 12,000 to 15,000 miles.
Now that we’ve delved into various factors that can lead to the check engine light, let’s look at resetting the light.
How to Reset the Check Engine Light
If you notice the check engine light after oil change services, consider contacting a mechanic who will reset your car’s computer to remove the worrying light.
Here’s what a mechanic will do using an OBD II scanner:
- Locate the OBD-II port beneath the dashboard near the steering column.
- Plug the OBD scanner into the port.
- Turn the ignition on without starting the engine. The scanner will read and display diagnostic trouble codes associated with the issue.
- Identify and repair the components indicated by the codes.
- Clear the codes from the system to reset the check engine light.
The appearance of the check engine light after oil change procedures can stem from various factors, from low oil levels to loose components. Understanding these causes can help you address issues correctly.
Need help keeping your oil system running smoothly?
AutoNation Mobile Service is a mobile car repair and maintenance solution offering upfront pricing and stellar customer service. Our expert mechanics will tackle any car maintenance issues right in your driveway.
Fill out this form to book an appointment for any issues related to the check engine light or other car services!