Why Your Check Engine Light is On After an Oil Change

For automobile owners, nothing is more unpleasant than seeing that dreaded “check engine” light on the dashboard. When the check engine light comes on, it just implies that anything could be wrong with the engine.

This warning light will not indicate a major problem if it appears after an oil change. It’s pointing to a small mistake you made when changing the oil, like adding too much oil to the engine and not seating the cap and dipstick correctly. Keep in mind that the warning light will not go off instantly, even though you can fix the causes of the check engine light following an oil change.

What does a check engine light (CEL) mean?

Any onboard diagnostic system worth its salt will include a check engine light—also known as a malfunction indicator lamp, or MIL—in it. It signifies that your vehicle’s computer has identified a problem with the engine, emissions system, or transmission when it shows up on the dashboard.

What is the function of the check engine light?

This light serves as a warning, alerting you to a possible problem before it becomes worse and more costly to correct. Any number of problems, from a loose gas cap to a broken catalytic converter, can be indicated by the light. What will happen if you don’t figure out what’s triggering the engine warning light and fix it?

  • Increase emissions
  • Poor fuel economy
  • Potential engine damage

Who needs an oil change while the check engine light is still on?

After changing the oil, there are a number of things that could trigger the check engine light to go on. Loose oil filler caps, insufficient oil, poor oil pressure, or using the incorrect kind of oil are the most typical causes of the check engine light flashing following an oil change. Finding the source of the problem and fixing it properly should take precedence over simply turning off the light using a diagnostic scan tool.

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Oil level is low

One typical reason the check engine light stays on after changing the motor oil is a low oil quantity. The warning light will go on if, during maintenance, you use 4 liters of engine oil instead of the recommended 5 liters.

Inadequate lubrication, along with the light coming on, is a sign of low oil levels. The components of the engine that move back and forth will be impacted by this.

Putting in the wrong kind of oil

If you use synthetic motor oil instead of traditional, your car’s check engine light will go on. If you use the wrong grade of oil viscosity, the dashboard malfunction indicator light will go off. For example, sticking with a 10W30 after service instead of the recommended 0W30 will likely trigger the engine warning light.

Issues with oil pressure

In order to keep the engine well lubricated, the oil pressure is critical. Deteriorated oil pressure sensors, insufficient oil, faulty oil pumps, and leaks are among the several potential causes of low pressure.

Both the check engine light and the oil pressure light could come on if the engine isn’t getting enough lubrication due to a low oil level or a faulty pump. The oil pressure light and engine warning light can both be activated if the oil pressure sensor isn’t working properly and sending the wrong data to the vehicle’s computer.

Engine oil that is too full

Am I going to get a check engine light if I use too much oil? Just as the malfunction indicator bulb will be triggered by insufficient engine oil, it will also be triggered by excess oil. Reduced oil circulation, foamy oil, and elevated engine pressure are all symptoms of an overfilled engine. The CEL will be triggered by the engine control unit to inform you of the situation.

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Check that the oil dipstick is placed correctly.

To find out how much oil is in your engine, use the oil dipstick. There is a high probability that it is not seated correctly because you remove and reinstall it multiple times when you change the oil. The engine could be flooded with unfiltered air if it isn’t seated correctly. In such a case, the check engine light will be activated by the engine control unit.

Oil filler cap that is unsecured

When changing the oil in your engine, you’ll need to remove the top cover, which is called the oil filler cap, and pour in fresh oil. The engine’s air-to-fuel ratio can be thrown off if the oil filler lid isn’t snugly fastened. The computer in your vehicle will then activate the check engine light to let you know anything is wrong.

Resetting the Check Engine Light

After you replace the oil, here’s how to disable the check engine light. Identifying the root cause of the warning light’s activation is the first step in diagnosing the vehicle. Subsequently, using a diagnostic tool, you can reset the malfunction indicator lamp as follows:

Find the on-board diagnostic input (OBDII) port under the vehicle’s steering wheel.
Put the diagnostic tool into the on-board diagnostic port (OBDII) of your car.
Press the ignition switch to the ON position, but refrain from starting the vehicle. Later on, retrieve the recorded error messages.
Make sure you understand the code and fix anything that isn’t fixed.
To reset your car’s engine warning light, delete the stored codes.
Keep in mind that the lights will come back after a few driving cycles if you only clear them without fixing the underlying problems.

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There are a number of possible causes for the check engine light to illuminate following an oil change. Possible causes of the check engine light coming on after oil change include: oil filler caps that are too loose, low-quality oil filters, an oil dipstick that isn’t sitting correctly, insufficient engine oil, too much oil, low oil pressure, or using the incorrect engine oil. Promptly identifying the vehicle’s problem and fixing it are of utmost importance.

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