Emissions tests are not required in 17 states but every other state Including the District of Columbia and Puerto Rico require some degree of emissions testing on a semi-regular basis. The point of emissions testing is to make sure that your vehicle isn't putting out harmful chemicals in the exhaust at a level that has been determined dangerous by the EPA. Most vehicles contain parts like a catalytic converter and so on as a method of preventing these chemicals from spewing out in the exhaust. That said, things can go wrong with your vehicle in a way that makes the amount of toxic chemicals you're producing too great to pass emissions tests. If that's a concern, we can let you know exactly what you need to do to ensure that you pass your emissions test.
How to Pass an Emissions Test
Most emissions testing is fairly straightforward and stress-free these days. If your car was made in 1996 or sooner then a technician can hook up an on-board diagnostic tool, an OBD2 scanner, to figure out the emissions levels from your vehicle. This will be done in conjunction with a visual inspection. On top of that several systems will be tested at the same time and the overall emissions system will be determined as a pass or fail.
There are a few things you can do to up your chances of passing your emissions test if you're concerned that something may be off in your vehicle.
Use a Fuel Additive
Some drivers consider fuel additives to be a useless expense that provides no discernible benefit. However, the purpose of most fuel additives is to make your fuel burn more cleanly and that include cleaning up carbon deposits in your exhaust and intake.
There's an attitude made by CRC That's actually called guaranteed to pass emission test formula. It only costs about $13 and they guarantee double your money back if you don't pass your emissions test after using it. The number of mechanics have reviewed it online and do support the idea that it will help you pass an emissions test, so it's definitely worth a try.
All you need to do is empty a bottle of the formula into your tag next time you fill up and then try that as normal until you run through the whole tank of gas. Refill as normal and you are ready to take your emissions test. Be sure to follow the directions exactly, and hopefully everything will work out for you.
Warm up the Engine
Your engine burns fuel as clean as it can when it's already warmed up. To maximize your chances of passing a test make sure you've driven around for a while before you take one. Get about 20 or 30 minutes of driving in before you head to the inspection to ensure your engine is in prime operating condition. A properly warmed engine will release fewer hydrocarbons from the tailpipe. To improve your chances even more, do it on a colder day. A warm engine on a cold day burns fuel even more efficiently.
Change Your Oil
If you have old, contaminated oil then the fumes from that are being burned during your combustion process in your engine. This will increase the emissions during an emissions test. It's best to save yourself the trouble and change the oil beforehand so that you have no additional contaminants to worry about.
Inflate Your Tires
As weird as this sounds, having tires that are properly inflated can affect your emissions test. If your tires aren’t properly inflated, it slightly reduces the overall efficiency of your vehicle. Think of how hard it is to drive on a flat tire for instance. When your tires are filled to the precise right amount then it reduces the stress on the engine and causes your car to run a little more cleanly than normal. It may not make a huge difference, but it does make a difference.
Check the Check Engine Light
The check engine light on your dashboard can go off for any number of reasons. A lot of drivers will ignore a check engine light if it's been on for a while and doesn't seem to be related to anything that affects the overall performance of the vehicle. That's bad news when you go in for an emissions test. In most tests, having a check engine light on your dashboard is an automatic fail. So, if the light is on your dashboard you're going to need to find out why before you go in for your emissions test.
A mechanic should be able to piece together why the light is on and hopefully get to the root of the problem for you.
Which States Require Emissions Testing?
Not every state requires that your car even gets emissions tested. Some do however and there are different schedules for how this needs to be done.
Alabama: There is no emissions testing required in the state of Alabama.
Alaska: Every two years you need to have your car emission tested in Alaska if you live in Fairbanks or Anchorage. Anywhere else in the state and it's not required.
Arizona: Emissions testing is a little complicated in Arizona. There are two places divided as Area A and Area B in Arizona. You need to have inspections in both before you can register your vehicle. Area includes Maricopa, Yavapai, and Pinal counties. Area B is some parts of Pima County
Vehicles made before 1966 are exempt. In Area B Vehicles made before 1980 are exempt, unless they are diesel. There are also some weight restrictions for vehicles in Area A that you need to be aware of. It's best to check with the Arizona Department of Environmental Quality to find out for sure.
Arkansas: No emissions tests are required.
California: Smog inspections are required for every vehicle in California except motorcycles or those made before 1976, or diesel powered before 1996 that way over 8500 lbs. Vehicles that are 8 years old or less are exempt from the smog requirement for registration renewal. Some counties only require smog certification in certain areas.
Colorado: Emissions testing is required when registering or selling vehicles in many counties.
Connecticut: Any vehicle made since 1968 has to have an air pollution control device. Vehicles are inspected biennially.
Delaware: All vehicles manufactured since 1968 are required. If they've been made in the last five years, they are exempt.
District of Columbia: Vehicles since 1968 are tested biennially. Zero emission vehicles are exempt as are new vehicles that have a certificate of origin.
Florida: No emissions tests are required.
Georgia: Most counties require annual emissions inspection before registration.
Hawaii: No emissions tests are required.
Idaho: Emissions tests are determined by local ordinances and are required in Ada County and Canyon County.
Illinois: Annual testing is required for vehicles in many counties but not all.
Indiana: Emissions testing requirements are determined on a county-to-county basis.
Iowa: No emissions tests are required.
Kansas: No emissions tests are required.
Kentucky: Some cities and counties do require it, but not all.
Louisiana: Tests are conducted on an annual basis.
Maine: Emissions testing required for original registration as well as renewals in Cumberland County.
Maryland: Vehicles need an exhaust emissions test and equipment every two years. Vehicles made in 1996 and after have to pass an OBD test. You have to carry the inspection certificate that you guys at all times in the vehicle.
Massachusetts: Vehicles made in 1997 and newer are tested annually for safety and emissions. From 1999 and sooner they need annual emissions tests that cost $29.
Michigan: No emissions tests are required.
Minnesota: No emissions tests are required.
Mississippi: No emissions tests are required.
Missouri: Emissions tests are conducted in many counties. Vehicles older than 1995 are not inspected.
Montana: No emissions testing is required.
Nebraska: No emissions testing is required.
Nevada: Vehicles in some urban and suburban portions of Clark & Washoe Counties are required to be tested. Smog checks are required on all vehicles made since 1968. New vehicles on first or second registration are exempt. Tests are required annually with registration renewal.
New Hampshire: Vehicles from 1996 and newer have to pass an onboard diagnostic system check meeting EPA standards.
New Jersey: Most vehicles in New Jersey require an emissions inspection.
New Mexico: Emissions tests are required by county or municipal ordinance only. Albuquerque in Bernalillo County are the only places that currently require these tests.
New York: Emissions tests are done annually.
North Carolina: About one-fifth of the counties in North Carolina require emissions testing.
North Dakota: No emissions tests are required.
Ohio: Vehicles in many counties in Ohio require emissions testing, but not all of them.
Oklahoma: Emissions tests are not required.
Oregon: Vehicles made since 1975 require emissions inspections around Portland. In the Medford Ashland area vehicles in the last 20 years need to be emissions tested.
Pennsylvania: Most vehicles in Pennsylvania require emissions inspections. There are a number of conditions That apply. You can check with Drive Clean Pennsylvania for more information.
Rhode Island: Emissions tests are required for all vehicles newer than 25 years of age, electric vehicles, new vehicles, and others that meet certain requirements.
South Carolina: No emissions tests are required.
South Dakota: No emissions tests are required.
Tennessee: Numerous counties require emissions testing in Tennessee but not all of them. Vehicles older than 25 years are exempt.
Texas: Certain vehicles in certain counties must pass inspection prior to registration.
Utah: Most vehicles manufactured since 1968 must pass an emissions test.
Vermont: As part of the California Low Emission Vehicle program, Vermont requires dealerships to sell the cleanest cars available to Vermont residents. All vehicles are inspected upon purchase to ensure they meet vehicle emission control standards.
Virginia: Vehicles are inspected on a biennial basis as long as they weigh less than 10,000 pounds and are more than four years old. Hybrid and electric vehicles don't count, and neither do motorcycles.
Washington: Vehicles that are between 5 and 25 years old registered in many counties must pass an emissions inspection every two years.
West Virginia: No emissions tests are required but the exhaust system will be checked during safety inspections.
Wisconsin: In most counties' vehicles require inspection within 90 days of registration.
Wyoming: No emissions testing is required
Puerto Rico: Emissions control systems will be inspected as part of a periodic 6-month inspection.
What Happens If I Fail My Emissions Test?
If you fail your emissions test in the DMV will not allow you to register your vehicle. That means you can't get any legal plates to drive your vehicle. When you do fail, they will give you a complete report on the test and explain to you why it was you failed. That can help you figure out what went wrong in what you can do to fix it.
Once you've made the necessary repairs you may be able to get a retest done for free. Some places will do this, so you should research at a time to find out which location near you will offer you a free retest. Because testing is so much more widespread, they do look for a competitive edge so some will offer you a retest for free. An emissions test is not super expensive, often between $15 and $25 depending on where you live, but why spend that money again if you don't have to.
In some states you could get a free retest offered right away if you failed, they should tell you what went wrong with your vehicle in the first place. I failed emissions test can be the result of several different problems including:
- A bad fuel injector
- A bad catalytic converter
- Bad air injection system
- Oxygen sensor malfunction
- Ignition system defense
- Vehicle vacuum leak
The range of prices associated with repairing these could be quite unpredictable but at least you'll know where you need to look and what you need to do if you do fail the test. Getting it fixed as soon as possible is the only way to legally drive your car again.
The Bottom Line
Emissions testing may seem like a nuisance, but it is part of an effort to ensure that your vehicle is running cleanly and you're doing what you can to protect the environment. Remember, with upwards of 1.4 billion cars on the road in the world, it's everyone's responsibility to make sure that we're doing what we can to lower emissions and help keep the air clean whenever we can. Emissions testing is one small part of that.