What Is an Emissions Test and How Can a Diagnostics Scanner Help?

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Internal combustion engine or gas-powered vehicles, even hybrid vehicles to some extent, produce exhaust emissions when operational as fuel burns. Altogether, the vehicle emissions system is a complex network of components designed to reduce harmful or toxic emissions from that process. It removes waste gases like carbon monoxide, nitrogen oxides, particulates, hydrocarbons and other pollutants and essentially cleans them so the vehicle outputs healthier air. Without that protection, they could release into the Earth’s atmosphere causing a host of issues, including air pollution and major health problems.

The good news is that modern vehicles have fairly robust emissions and exhaust systems that include a lot of protections. But over time, those systems can break down and that’s why some states require emissions tests, such as New York, California, Arizona, Georgia, Massachusetts, Missouri, North Carolina, Tennessee, Texas, Washington, and more. The state conducts and monitors tests to make sure vehicles in use are not producing toxic emissions.

Testing is done in stages, usually set by the state in question. For example, you may need to get a test done on your vehicle when you move to one of the regulated states. You may also need to get it done when you renew your license or registration or transfer ownership of your vehicle.

What Is an Emissions Test?

The test itself, or rather what’s being tested is pretty simple. During an emissions test the quality of the air coming out of the exhaust will be measured. This is usually done by connecting the vehicle to specialized equipment that can measure the emissions while the vehicle is operational. A true test involves checking those emissions at varying speeds, essentially analyzing how the chemical components change as the vehicle is under heavy use. A test failure doesn’t necessarily mean you’re in trouble, but it does mean the vehicle in question will need servicing.

If you were to just take the vehicle into the appropriate service centers for the test blindly, you might not know what to expect. You won’t know if you’ll pass or fail, especially with an aging vehicle that may have been used quite a bit over the time since it was last tested, if at all. But that’s precisely where a diagnostics scanner comes into play.

You can use a diagnostics scanner, an OBD2 scanner, to check emissions and see if the vehicle is going to pass or fail. That also gives you the opportunity to fix the problem before an official test, whether you do that at home or bring your vehicle to a professional repair team.

How a Diagnostics Scanner Can Help

In most cases, if something is wrong with the emissions system you will see the check engine light come on. But it’s entirely possible that won’t happen. There are other warning signs, for example, you might notice a raw fuel smell, worsening engine performance or strange odors.

But it’s much easier to get out an appropriate diagnostics scanner, like the Innova 5610 and run an emissions test of your own. You can check emissions or do a smog test directly. You can also test individual components and systems, including the Exhaust Gas Recirculation (EGR) system, Positive Crankcase Ventilation (PCV) valve, catalytic converter, Evaporative control system (EVAP), or oxygen sensor. An O2 sensor test, EVAP test, or all-systems test will return the results that you can use to determine what’s going on, if there’s anything wrong.

By pairing the Innova 5610 with your phone through the RepairSolutions2 app, you can also see and reference a host of additional diagnostics information to inform your next move.

Why Emissions Checks Are Important Everywhere

While many states require regular emissions tests, there are a few that don’t — Florida, for example. But you should still be checking your system every so often even if it's not officially mandated. Emissions failures can cause worsening fuel efficiency, via declining performance, which would mean you’re burning more gas and spending more money to fuel up and that’s never fun.

Beyond that, performance in general could suffer, potentially leading to a full engine failure, especially in the case of failing O2 sensors, and issues with the EVAP system. You can start to see that engine emissions problems aren’t just a health complication, though that’s a huge element. The emissions system is also vital to keeping your car running optimally, which is a big deal if you want it to last for years to come.

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