Will a Car Pass Smog with Check Engine Light On?

The answer to this question is: it depends.

In most states, a car with a check engine light on will not pass a smog test. The check engine light is an indicator that there is something wrong with the car’s emissions system. This could be a minor problem, such as a loose gas cap, or it could be a more serious problem, such as a faulty catalytic converter.

If the check engine light is on, it is important to have the car inspected by a mechanic as soon as possible. The mechanic will be able to diagnose the problem and make the necessary repairs. Once the repairs have been made, the car should be able to pass a smog test.

What are the exceptions?

There are a few exceptions to the rule that a car with a check engine light on will not pass a smog test. These exceptions include:

• If the check engine light is on due to a minor problem, such as a loose gas cap, the car may still be able to pass a smog test.
• If the car is a newer model, it may be equipped with an on-board diagnostic (OBD) system that can store and retrieve emissions data. This data can be used to determine if the car is meeting emissions standards, even if the check engine light is on.
• Some states have a “smog check waiver” program that allows cars with certain types of emissions problems to pass a smog test. These waivers are typically only available for cars that are older than a certain age or that have a certain number of miles on them.

What should you do if your check engine light is on?

If your check engine light is on, the best thing to do is have the car inspected by a mechanic as soon as possible. The mechanic will be able to diagnose the problem and make the necessary repairs. Once the repairs have been made, the car should be able to pass a smog test.

In the meantime, you can try to determine if the problem is minor by checking the following:

• Check the gas cap to make sure it is tight.
• Check the air filter to make sure it is clean.
• Check the spark plugs to make sure they are not fouled.

If any of these items are not in good condition, you can try replacing them yourself. However, if the problem is more serious, it is important to have the car inspected by a mechanic.

Conclusion

In most cases, a car with a check engine light on will not pass a smog test. However, there are a few exceptions to this rule. If you are unsure whether or not your car will pass a smog test, it is important to have it inspected by a mechanic.