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Program Information

The Purpose of E-Check

What is the E-Check program and why do we have it?

In January 1996, the State of Ohio began a new vehicle emissions testing program, E-Check, designed to identify motor vehicles that emit excessive levels of pollutants into the air. Among the other emissions control options considered by the legislature, E-Check was the most cost-efficient measure to reduce the volatile organic compounds (VOCs) that form ground-level ozone, or smog. The program currently tests cars in seven Ohio counties.

At the time it was implemented, E-Check used the I/M 240 test, a 240-second transient test during which a vehicle is driven on a dyne (treadmill) and its tailpipe emissions are measured. In 2000, the I/M 240 test was replaced with Acceleration Simulation Mode (ASM) 2525. ASM 2525 is similar to I/M 240 but is perceived to be less stressful on the vehicle. Testing programs, like E-Check, that employ one or more of these tests are referred to by U.S. EPA as "enhanced" programs.

In January 2004, a new, federally mandated test known as On-Board Diagnostics (OBD II) was implemented. OBD II is required for newer vehicles, while ASM 2525 is still used for older vehicles. For more information on OBD II .

Laws and Rules that Govern the E-Check Program

  • Federal Requirements
  • State Requirements
  •   Other Federal Resources
  • Other State Resources

Why do only seven counties have E-Check?

U.S. EPA classifies areas based on the National Ambient Air Quality Standards (NAAQS) that were initiated as a result of the Clean Air Act Amendments of 1990. For any given area nationwide, the air quality is monitored on an hourly basis for ground-level ozone, better known as smog. Ozone levels that exceed the NAAQS for a metropolitan statistical area (population more than 100,000) are categorized into one of five nonattainment levels: marginal; moderate; serious; severe; or extreme. Individual states are then required to initiate basic emissions testing in any nonattainment area ranked moderate and above.

On April 15, 2004, U.S. EPA announced that 33 Ohio counties were out of attainment for the eight-hour ozone standard. In order for Ohio to meet the eight-hour standard, additional air pollution control measures may be necessary in these counties.

Under the new eight-hour ozone standard, the following counties in the Cleveland and Akron area are required to continue the E-Check program: Cuyahoga; Geauga; Lake; Lorain; Medina; Portage; and Summit counties.     

What are the health effects from smog?

The U.S. Environmental Protection Agency has found that tailpipe emissions from cars and trucks account for at least one-third of the air pollution in the United States. Exposure to the pollutants found in vehicle emissions have been shown to cause serious health problems. Although today's cars emit much less pollution than in the past, there are more cars on the road traveling more miles than ever before. Ohio E-Check is an important initiative aimed at improving the air we breathe. Modeling by Ohio EPA shows that emissions testing removes a minimum of 74 tons per day of volatile organic compounds (VOCs), carbon monoxide (CO) and nitrogen oxides (NOx).


Carbon Monoxide

Carbon monoxide is a colorless, odorless, poisonous gas emitted from the vehicle's exhaust as a result of an incorrect air and fuel mixture resulting in incomplete combustion. Carbon monoxide interferes with the blood's ability to carry oxygen to the brain, heart and other tissues. Unborn or newborn children and people with heart disease are in the greatest danger from this pollutant, but even healthy people can experience headaches, fatigue and reduced reflexes due to CO exposure. Read more about carbon monoxide from U.S. EPA.


Ozone is the major component in what we know as smog at ground level. Ozone is not emitted directly into the air but is produced in the lower atmosphere as a result of chemical reactions between oxygen and oxides of nitrogen in the presence of sunlight, especially in warm weather. This reaction normally results in a constant cycle where ozone is created and immediately broken down back into oxygen and NOx. However, hydrocarbons and other VOCs exist in the air which prevent ozone from breaking down, therefore increasing ozone concentrations. In the body, ozone reacts with lung tissue, causing inflammation of the lungs. Ozone can cause harmful changes in breathing passages, decrease the lungs' working ability and cause coughing and chest pains. Even healthy people are found to be sensitive to ozone exposure. See how ozone is formed or read more about ozone from U.S. EPA.

Nitrogen Oxide

Nitrogen oxides (NOx) are produced when fuel is burned at excessive temperatures. These compounds are essential to ozone formation and are a health problem themselves. The effect of NOx exposure on the respiratory system is similar to that of ozone and sulfur dioxide. Read more about nitrogen dioxide from U.S. EPA.

Hydrocarbons (Volatile Organic Compounds)

Hydrocarbon emissions result from fuel that does not burn completely in the engine. Hydrocarbons are a type of volatile organic compound (VOC). VOCs are chemicals containing hydrogen, carbon and possibly other elements that evaporate easily. Hydrocarbons and other VOCs contribute to the formation of ozone by increasing the amount of nitric dioxide in the air, which then combines with oxygen molecules to produce nitrogen and ozone. A number of exhaust hydrocarbons are also toxic, with the potential to cause cancer. Read more about hydrocarbons from U.S. EPA.

Particulate Matter

Particulate matter includes microscopic particles and tiny droplets of liquid. Because of their small size, these particles are not stopped in the nose and upper lungs by the body's natural defenses but go deep into the lungs, where they may become trapped and cause irritation. Exposure to particulate matter can cause wheezing and similar symptoms in people with asthma or sensitive airways. Particulate matter can serve as a vector for toxic air pollutants. Read more about particulate matter from U.S. EPA.

How do we reduce risk from emissions?

How can we reduce the risk of health problems caused by exposure to vehicle emissions? Not driving is the obvious suggestion, but that isn't always practical. Instead, you can carpool, use mass transit, bicycle or walk whenever possible. The fewer vehicles on the highway, the fewer pollutants emitted in the air.

Another way to reduce vehicle pollution is by practicing good vehicle maintenance. Your vehicle owner's manual has a suggested maintenance schedule. Vehicles pollute the least amount when they are new. Over time, the emission control systems degrade and pollution increases. Keeping your vehicle well-maintained with regular tune-ups will prolong the efficiency of your engine and its emission control systems. Keeping filters and catalytic converters clean will decrease fuel consumption and help assure that the pollution control devices are in good working order.

Don't overfill or top off your vehicle's gas tank. Gasoline that spills, as well as fumes that escape, react with nitrogen oxides and sunlight and create smog.

Stop your vehicle's engine if it is idling at a drive-up window or in traffic jams and limit warm-up time in the winter. Contrary to popular belief, turning off and starting an engine uses less gasoline than letting it idle for 30 seconds.

Keeping tires properly inflated and wheels aligned not only improve fuel economy but help reduce air pollution.

Most importantly, do not remove or tamper with pollution controls.  

What does the future hold?

While we have made significant achievements in improving air quality over the past 20 years, air pollution from automobiles remains a challenge. The number of registered vehicles in Ohio has increased 125 percent since 1970. This increased number of vehicles overshadows the benefits of today's cleaner-burning vehicles. The Ohio E-Check program is essential to identifying those vehicles in need of emission repair so that they can be made to run cleaner and more efficiently.

E-Check Annual Reports

The annual reports for the Ohio E-Check program present an overview of E-Check activities conducted and highlight program contributions toward improving Ohio's air quality. View E-Check annual reports.

E-Check Customer Satisfaction Surveys

Gray Market/Engine Switch

Engine-switched vehicles

In an engine-switched vehicle, the original engine has been replaced with a different engine. This different engine may have been offered in the same model year as that vehicle or it may be from another year or manufacturer.

Engine-switched vehicles are tested by the model year in which the vehicle was titled because the vehicle was certified to meet emission requirements for that year.

These vehicles must meet the inspection requirements for the titled model year, including the tampering portion of the test. If older, less clean technology is put into a vehicle, it de-certifies the vehicle, promotes poor performance, and violates the Clean Air Act.

Establishment of engine-switching procedures

U.S.EPA established engine-switching procedures to comply with the federal Clean Air Act. The following is an excerpt from U.S. EPA's Engine-Switching Fact Sheet:

"A 'certified configuration' is an engine or engine-chassis design which has been 'certified' (approved) by EPA prior to the production of vehicles with that design. Generally, the manufacturer submits an application for certification of the designs of each engine or vehicle it proposes to manufacture prior to production. The application includes design requirements for all emission related parts, engine calibrations, and other design parameters for each different type of engine (in heavy-duty vehicles), or engine-chassis combination (in light-duty vehicles). EPA then 'certifies' each acceptable design for use in vehicles of the upcoming model year.

"For light-duty vehicles, installation of a light-duty engine into a different light-duty vehicle by any person would be considered tampering unless the resulting vehicle is identical (with regards to all emission related parts, engine design parameters, and engine calibrations) to a certified configuration of the same or newer model year as the vehicle chassis, or if there is a reasonable basis for knowing that the emissions are not adversely affected as described in Memo 1A*. The appropriate source for technical information regarding the certified configuration of a vehicle of a particular model year is the vehicle manufacturer.

"For heavy-duty vehicles, the resulting vehicle must contain a heavy-duty engine which is identical to a certified configuration of a heavy-duty engine of the same model year or newer as the year of the installed engine. Under no circumstances, however, may a heavy-duty engine ever be installed in a light-duty vehicle."

*Memo 1A is a federal document that allows the use of after-market parts on vehicle emission systems.

Despite these clear guidelines, proper engine switches are uncommon. Usually, a 1980s vehicle has had a 1970s motor installed because of availability and cost. Such a vehicle has been de-certified and will likely fail an emissions test.

Rebuilt vehicles

A rebuilt vehicle was given a salvage certificate of title and has since been refurbished and passed the Ohio State Highway Patrol Inspection. This vehicle type can be titled in the model year that the majority of the parts are from or that matches the outward appearance of the vehicle. This vehicle type can also be titled with the original year and Vehicle Identification Number (VIN) but will have a notation that is was salvaged.

Rebuilt vehicles are tested according to their titled model year because they were certified to meet emission requirements for that year (if the vehicle is assigned a new VIN by the Ohio State Highway Patrol, it will be treated as a self-assembled vehicle). These vehicles met emissions standards when manufactured but were later salvaged. When an individual makes a rebuilt vehicle roadworthy, it also needs to be emissions-worthy.

Gray-market vehicles

A gray-market vehicle was built for sale and use in another country and later imported into the United States. There may or may not be a U.S. EPA-certified version of the vehicle. These vehicles either receive an "Import Waiver" from U.S. EPA and U.S. Customs or were retrofitted with emissions equipment to meet emissions standards for that model year. Even if a vehicle has been issued a U.S. EPA Import Waiver, the vehicle is not exempt from applicable state or local emission requirements. These conditions are stated directly on most import waivers (usually the third paragraph).

Gray-market vehicles are tested by their model year because the importer chose to either bring the vehicle into compliance with U.S. standards or to receive waivers and accept the stipulated conditions when the vehicle was brought to the U.S. Gray-market vehicles are required to meet the same emissions standards as a U.S.-certified version of the vehicle from the same year. If the U.S. EPA-certified version of this vehicle has a catalytic converter, the gray-market vehicle will be required to have a catalytic converter (or sealing gas cap, air pump and air system, evaporative system, etc.). If there is no U.S. EPA-certified version, the vehicle shall, at a minimum, have a catalytic converter and a sealing gas cap if the manufacturer used that strategy on a comparable, same-year U.S. EPA-certified model that fits the same vehicle class. If the vehicle has no comparable U.S. version, U.S. EPA shall be consulted as to whether a catalytic converter would have been installed on the vehicle upon importation to conformity with federal emissions requirements.

For more information about gray-market vehicles, please visit the following websites:

Self-assembled vehicles and kit cars

A self-assembled vehicle is made from parts of other automobiles or from after-market parts. A self-assembled vehicle is titled in the year in which it is brought to the Ohio State Highway Patrol for inspection. It is assigned a Vehicle Identification Number (VIN) by the patrol. The self-assembled vehicle can be considered "homemade" and some are titled that way.

A kit car also is titled in the model year in which it is inspected by the Ohio Highway Patrol. Kit cars often include dune buggies and fiberglass body replicas. Kit cars are like self-assembled vehicles except they are usually fiberglass bodies and come with instructions for assembly.

Kit cars and self-assembled vehicles are tested according to the titled year unless the engine year can be confirmed. This confirmation of engine year is the responsibility of the vehicle owner. The proof should be a letter from the dealer or manufacturer of the engine. Other forms of proof will be considered on a case by case basis.

Once the engine year is documented, schedule an appointment with the local Ohio EPA E-Check field office. Arrangements will be made for you to meet with an Ohio EPA representative at a designated location. You will need to bring your documentation and the vehicle with you. It is helpful if you can point out where the engine block casting number is located.

If your vehicle's engine year is within the scope of the emissions testing program, you will be given a form that allows the vehicle to be tested using the proper standards for that engine year. You will need to present this at the testing site each time the vehicle is tested.

If your vehicle's confirmed engine year is too old to fit into the scope of the emissions testing program, you will be given a permanent exemption.

Volkswagen Information

Which vehicles are affected?

Jetta 2009-15, Jetta Sportwagen 2009-14, Beetle 2012-15, Beetle Convertible 2012-15, Audi A3 2010-15, Golf 2010-15, Golf Sportwagen 2015, Passat 2012-15.

Am I still required to have an emissions test?

Yes, remain on your current testing cycle.

Can I continue to drive my vehicle?

Yes, EPA's Notice of Violation announcement makes it clear these vehicles are safe and remain legal to drive.

Is there anything I need to do?

No, owners of these vehicles do not need to take any action at this time. It will be important to have the repairs completed when the manufacturer sends you a recall notice.

Related Information

U.S. EPA news release.
EPA, California Notify Volkswagen of Clean Air Act Violations

Additional information from U.S. EPA.