Will Car Pass Emissions with Check Engine Light On?
Understanding the Check Engine Light
The check engine light is a dashboard indicator that illuminates when the vehicle’s electronic control module (ECM) detects a problem within the vehicle’s emission control system.
There are numerous reasons why the check engine light may turn on, ranging from minor issues such as a loose gas cap to more severe problems like a faulty oxygen sensor.
Emissions Test Requirements
Emissions tests are conducted to verify that a vehicle meets the allowable limits for certain pollutants, including hydrocarbons, carbon monoxide, and nitrogen oxides.
The specific requirements for emissions testing vary by state and locality. However, most emissions tests involve connecting the vehicle to a diagnostic tool that monitors the vehicle’s emissions output.
Impact of Check Engine Light on Emissions Test
The presence of an illuminated check engine light generally indicates that the vehicle’s emission control system is not functioning properly.
As a result, vehicles with a check engine light on are often not eligible to pass an emissions test.
The reason for this is that the check engine light indicates a potential problem with the vehicle’s emissions system, which could lead to increased emissions.
Exceptions to the Rule
There are some exceptions to this rule.
In some cases, a vehicle with a check engine light on may still pass an emissions test if the problem is not related to the vehicle’s emission control system.
For example, if the check engine light is illuminated due to a loose gas cap, the vehicle may still pass an emissions test.
Steps to Take Before Emissions Test
If your vehicle’s check engine light is on, it is important to take the following steps before taking the vehicle for an emissions test:
- Determine the cause of the check engine light.
- Fix the problem if possible.
- Reset the check engine light.
Conclusion
In general, vehicles with a check engine light on will not pass an emissions test.
However, there may be exceptions to this rule.
It is important to determine the cause of the check engine light and take the necessary steps to fix the problem before taking the vehicle for an emissions test.
