Emissions testing determines the level of air pollutants emitted from the exhaust of a motor vehicle. The first emissions testing was done in California in 1966. Since then, many states began requiring testing for all registered vehicles. If a vehicle fails the emissions test, repairs must be done and the vehicle retested.

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Do All States Require Emissions Inspection?

Currently 32 states require some type of emissions inspection which depends on many factors. In Massachusetts, for example, vehicles over 15 years old require an annual check for visual smoke only. Some states require annual testing while others require it only once every two years.

Several factors may influence emissions testing requirements:

  • Vehicle age
  • Location (some states only require testing in urban areas or certain zip codes)
  • Vehicle weight and type
  • If the vehicle is registered in our out of state
  • Fuel type (for example,in North Carolina, non-gasoline powered cars are exempt)
  • Type of use (for example, in New Jersey, taxis must be inspected annually)

Emissions.org provides a state-by-state breakdown of vehicle emission testing requirements.

What Does Emissions Testing Check For?

Each state determines its own testing specifications. Depending on the testing apparatus, emissions testing can detect levels of hydrocarbons, nitrogen oxide, carbon monoxide, carbon dioxide, and emissions from evaporation.

Is Emissions Testing The Same As Vehicle Safety Inspection?

Emissions testing is separate from vehicle safety inspection in most states. Requirements and testing facilities may be independent for emissions and safety. Still, some testing locations might be qualified to perform both inspections.

How Much Does Emissions Testing Cost?

The cost of emissions testing varies from state to state. Typical costs range from $15 to $25. If testing is required annually, the cost is generally lower.

What Happens If My Car Fails An Emissions Test?

Some states offer a free retest if your vehicle fails an initial emissions test. In the states that require emission testing, your vehicle must be repaired to meet emission standards. Repair assistance to low income earners is available in some states.

What Causes Emissions Testing Failure?

Many mechanical problems can cause a vehicle to emit excess pollutants. For example, a faulty fuel injection can lead to a rich fuel mixture (too much fuel, not enough air). Rich fuel mixtures tend to lead to high carbon dioxide levels.

The air injection system forces fresh air into the exhaust. If this system fails, emissions testing may detect high levels of hydrocarbons or carbon monoxide.

Other problems that can lead to emissions testing failure are oxygen sensor malfunction, ignition system defects, and vehicle vacuum leaks.

How Much Does It Cost To Get Emissions Problems Repaired?

The repair costs to correct elevated emissions varies depending on the problem and the vehicle make and model. Transmission repairs might cost several hundred dollars while an oxygen sensor replacement might be around $100.

A pre-purchase car inspection gives you detailed information about the condition of any car in the country. Arrange a car inspection with CARCHEX today.