Can a Car Pass Smog with the Check Engine Light On?

The Answer is: It Depends

Whether or not a car can pass smog with the check engine light on depends on the reason for the light being on. If the light is on due to a minor issue that does not affect the emissions of the car, then it may still be able to pass smog. However, if the light is on due to a major issue that does affect the emissions of the car, then it will likely fail smog.

Minor Issues That May Not Affect Smog

Loose gas cap
Faulty oxygen sensor
Evaporative emissions control system leak

Major Issues That Will Likely Affect Smog

Catalytic converter failure
Engine misfire
Excessive exhaust emissions

What to Do if Your Check Engine Light is On

If your check engine light is on, it is important to have it diagnosed as soon as possible. This will help you to determine if the issue is minor or major, and if it will affect your ability to pass smog.

If the issue is minor, you may be able to fix it yourself or have it fixed by a mechanic. If the issue is major, you will need to have it repaired before you can pass smog.

How to Pass Smog with the Check Engine Light On

If you have a major issue that is causing your check engine light to be on, you will need to have it repaired before you can pass smog.

Once the issue has been repaired, you will need to have your car smog tested again. If the repairs have been successful, your car should now pass smog.

Conclusion

Whether or not a car can pass smog with the check engine light on depends on the reason for the light being on. If the light is on due to a minor issue, then it may still be able to pass smog. However, if the light is on due to a major issue, then it will likely fail smog.