HOW WE TEST || WHY WE TEST || TESTING TIPS || FAQ

HOW WE TEST

Depending on the year of your vehicle, Clean Air Car Check uses different types of emissions tests.  All vehicles receive a Gas Cap Pressure Check, which tests to see if a vehicle’s gas cap is effectively keeping fuel vapors from escaping.  Fuel evaporation is a major cause of ground level smog and a properly functioning gas cap improves gas mileage by preventing fuel waste.

The On-Board Diagnostics (OBD) Test is the most common test procedure and is used in vehicles that are model year 1996 or newer.  During this simple test, data is downloaded from the vehicle’s on-board computer to check for emissions equipment malfunctions.  An OBD scanner is attached to a plug under the vehicle’s dashboard.

The Inspection and Maintenance (I/M 93) Test is used for vehicles with model years 1981 through 1995 or newer.  During this test, an inspector drives the vehicle on a treadmill device called a dynamometer.  The test simulates driving on a road.  While driving, the car’s tailpipe emissions are captured and analyzed to evaluate the effectiveness if the vehicle’s emission control equipment.

The Single Idle Speed (BAR 90) Test is used in vehicles from 1976 to 1980.  A metal probe is inserted into the vehicle’s tailpipe while the vehicle idles to sample the exhaust stream.  At the same time, a sensor is placed on the hood of the vehicle to measure the engine speed.  The probe measures the vehicle’s emissions and they are analyzed to whether or not the vehicle’s emission control equipment is working properly.

WHY WE TEST

Motor vehicle manufacturers are required to meet increasingly stringent pollution emissions standards.  Vehicles that are not properly maintained or that have malfunctioning emission control systems often exceed these standards.  Vehicle emissions testing identifies such vehicles. Repairs are then required to reduce the emissions that cause pollution. Just over 17% of the vehicles tested fail the initial vehicle emissions inspection. Identifying and repairing these vehicles has reduced ozone precursor emissions by more than 4,000 pounds per summer day. These repairs also improve the vehicle’s performance and fuel economy.

The vehicle inspection and maintenance program is a requirement of the 1990 federal Clean Air Act amendments and is part of the overall plan to improve air quality be reducing hydrocarbons and nitrogen oxides in Lake and Porter counties.  Emission testing improves air quality by ensuring emission control are working properly. 

TESTING TIPS
Model years 1976 – 1995
Model years 1996 and newer

Model years 1976 – 1995

Fully warm up your vehicle before testing.  If possible, drive your vehicle at highway speed for at least 15 minutes prior to visiting an inspection station.

Make sure your brakes are in good condition.  Poor brakes are not only a safety hazard, but also make the vehicle very difficult to test on the equipment and may cause the vehicle to be rejected for testing.  If your vehicle is rear wheel drive, you must have functioning rear brakes.

Make sure your front wheel drive vehicle is properly aligned.  Poor front end alignment will make the vehicle difficult to test and may cause the vehicle to be rejected.



Model years 1996 and newer

Address service engine lights, especially during your warranty period. Read your owners manual for specific warranty information.

Don’t clear your codes. Clearing your codes or disconnecting your battery may cause you considerable grief and gas money trying to reset your monitors.
An OBD system is made up of monitors that test different components in the vehicle.  Some monitors run all the time (continuous monitors).  Others only run at certain times or if special conditions are present (non-continuous monitors).  If you clear your codes or disconnect your battery, your non-continuous monitors will no longer be ready and will require a variety of driving to get them to set again.  Manufacturers have different drive cycles for their vehicles, and some monitors are more difficult than other to set, particularly some 1996 and 1997 model year vehicles.  Monitors that are not ready may cause your vehicle to be rejected from the inspection. 

In order to avoid rejection for an inspection—don’t clear your codes!  If your check engine light is on, find out what Diagnostic Trouble Code (DTC) is causing the light to turn on, fix the problem and drive the vehicle until the light goes off.  When the light goes off, you know the problem is fixed.  If you are taking your vehicle to a professional repair technician have the repair technician return your vehicle with the light on.  After you take the vehicle through its drive cycle the light should go off and you will know the problem is fixed.

FREQUENTLY ASKED QUESTIONS
ABOUT EMISSIONS TESTING
ABOUT THE TESTING PROCEDURE

ABOUT EMISSIONS TESTING

A. The vehicle inspection and maintenance program is a requirement of the 1990 federal Clean Air Act amendments and is part of the overall plan to improve air quality be reducing carbon monoxide, hydrocarbons and nitrogen oxides in Lake and Porter counties.  Emission testing improves air quality by ensuring that vehicles' emission control are working properly.  This program has contributed to better air quality in Lake and Porter counties.

Q. Why is there a vehicle emissions program in Lake and Porter counties?

A. In the Clean Air Act Amendments of 1977, the United States Environmental Protection Agency designated Lake and Porter counties as nonattainment areas for ozone levels.  The counties were reclassified as a severe nonattainment area in the 1990 amendments to the Clean Air Act.  This classification requires areas failing to meet the National Ambient Air Quality Standards (NAAQS) for ozone to develop state implementation plans to attain and maintain the standard. Enhanced vehicle inspection/maintenance testing was put into place as a mandated control measure throughout the Greater Chicago area, which includes Lake and Porter counties, northeastern Illinois and southeastern Wisconsin.

Q. Why does my vehicle need to be tested?

A. Motor vehicles powered by gasoline are significant contributors to ground level ozone, or smog.  Therefore, testing of these vehicles ensures that emission controls are working properly and, if not working properly, testing ensures that vehicles owners make the appropriate repairs to aid in the reduction of ground level ozone.

Q. How often will my vehicle need to be tested?

A. Your vehicle is scheduled for testing every two years. The four most recent model years are exempt from testing. Odd model year vehicles are tested in odd-numbered years and even model year vehicles are tested in even-numbered years.  For example, a 1996 vehicle will be tested in 2000, 2002, 2004, 2006, 2008 and so on.  A 1997 vehicle will be tested in 2001, 2003, 2005, 2007 and so on. 

Q. When does my vehicle need to be tested?

A. Your vehicle will need to be tested before you can register or renew your vehicle’s registration with the Bureau of Motor Vehicles.

Q. How will I know when I am due for an emissions test?

A. The Indiana Bureau of Motor Vehicles (IBMV) currently notifies all motorists living in Lake and Porter Counties when their vehicles are due for testing.  If a test is needed, “EMISSION TEST REQUIRED” will be printed on their IBMV Application for Vehicle Registration Renewal notice.  This notice is mailed approximately two (2) months before the renewal deadline.  However, you do not have to wait to receive your notification in the mail before you take your vehicle in for an emissions test.  Vehicles can be tested in October, November or December for the following year’s test cycle.

The present vehicle testing schedule is determined by the month motorists are due to obtain their vehicle registration. The registration table is as follows:

Q. How much does the emissions test cost?

A. There is no charge for a vehicle emissions test in Indiana.

Q. Where do I take my vehicle for testing?

A. There are seven Clean Air Car Check stations in Northwest Indiana.  To determine which station is most convenient for you call the toll-free Clean Air Car Check hotline at 888-240-1684 or see LOCATIONS

Q. How do I know if the used vehicle I purchased requires testing?

A. A vehicle must receive a passing emissions test and provide proof to the Bureau of Motor Vehicles in order to register and license the vehicle.  We advise shoppers in the market for a used vehicle to call the toll-free Clean Air Car Check hotline to check the emissions status of a vehicle before they purchase it.  Using the Vehicle Identification Number (VIN), the testing record can be retrieved from the Clean Air Car Check database.  If the vehicle was previously tested in an Indiana county requiring emissions testing, we can tell the potential buyer if the vehicle passed the emissions inspection and when its most recent test was.

Q. What vehicles must be tested?

A. In the appropriate model year, passenger vehicles and light-duty trucks with a GVWR of less than 9,000 pounds and an engine displacement of over 200 cubic centimeters must be tested. 

Q. What if I do not comply with the vehicle emissions test?

A. If your vehicle is not in compliance you will not be able to be register or renew your vehicles' registration with the Bureau of Motor Vehicles.

Q. What vehicles are exempt?
           
A. Vehicles which are:

• The four newest model year vehicles,
• Model year 1975 and older,
• Powered by electricity or diesel fuel,
• Considered show cars and meet established criteria for a Show Car Exemption,
• Considered specialty or kit cars and meet established criteria for Specialty Exemption,
  
• Heavier than 9,000 Gross Vehicle Weight Rating (GVWR can usually be found on the vehicle’s door jamb),
• Ceremonial vehicles,
• Motorcycles,
• Off highway construction equipment, Registered as antiques,
• Have an engine displacement of less than 200 cube centimeters,
• Recreational vehicles, and
• Registered for farm use only (including tractors).

Q. Why aren’t diesel vehicles’ emissions tested?

A. Diesel exhaust contains relatively low levels of hydrocarbons (HC), carbon monoxide (CO) and nitrogen oxides (NOx), which are the pollutants that react with sunlight to form ozone.

Q. Why isn’t emissions testing required statewide?

A. Based on national air quality standards, federal law requires only Lake and Porter counties to have emissions testing because of ozone levels in those counties.

Q. What is my vehicle tested for?

A. The test consists of a fuel cap pressure test that checks to see if your fuel cap is doing its part to stop evaporative emissions from your gas tank.  Inspectors also check under your car to ensure that all the emissions monitoring components are intact.  The Clean Air Car Check will measure your vehicle for emissions of hydrocarbon (HC), carbon monoxide (CO) and nitrogen oxides (NOx).  High levels of these emissions indicate that a vehicle is not using fuel efficiently and, as a result, is contributing to poor air quality.

Q. What effect do hydrocarbons, carbon monoxide and nitrogen oxide have on the environment?

A. Hydrocarbons are unburned gasoline particles that contribute to the formation of ground level ozone, often referred to as smog.  Carbon monoxide is a colorless, odorless gas formed from partially burned fuel that can adversely affect mental function, visual focus, alertness, and can even cause death.  Nitrogen oxides, when mixed with other compounds, can contribute to ground level ozone, acid rain, water quality deterioration and global warming.

Q. What is ozone?

A. Ozone is an irritant produced from emissions from gasoline powered vehicles. It can cause eye and throat irritations, respiratory distress, and damage breathing passages, making it difficult for the lungs to work.

Q. How is ozone formed?

A. Ozone is formed near the ground in a photochemical process:

1) Gasoline, paints and solvents evaporate, thereby releasing hydrocarbons.

2) Cars and factories burn fossil fuels, releasing nitrogen oxide and
reactive hydrocarbons.

3) Heat and sunlight trigger a photochemical reaction between these emissions, transforming them into ozone.

ABOUT THE TESTING PROCEDURE

Q. How long will the test take?

A. Once the vehicle enters the first testing position, the three-step test should only take about ten minutes.

Q. Why do some of the lanes at the emissions test site move faster than others?

A. There are many reasons this may occur.  Fluid leaks, exhaust system problems, idling problems and insufficient warming of the vehicle’s engine can create problems with vehicle testing.  Customers without the proper paperwork such as the vehicle’s registration or the repair data form can also cause delays.

Q. Why do all of the car accessories have to be turned off?

A. Electrical accessories can interfere with the electronic sensing of the engine speed and can also adversely affect the test results.

Q. How does the test procedure work?

A. For model year vehicles 1981 – 1995, the emissions check has three steps. During the first step, an inspector will complete a basic visual inspection for leaking fluids and conditions that may present a safety problem.  The motorist will be asked for registration information so that the Vehicle Identification Number (VIN) can be verified.  The motorist will be asked to exit the vehicle and proceed to an enclosed, climate-controlled waiting area.  The lane inspector will then inspect for the presence of a catalytic converter and conduct a gas cap pressure check.

During the second step, the vehicle is placed on the dynamometer, a treadmill-like device, and secured in place.  The lane inspector will enter the vehicle and “drive” the vehicle, following a drive trace projector on a screen in front of the vehicle.  “Driving” the vehicle on the dynamometer simulates normal driving situations, including accelerating, decelerating, braking and stopping. The vehicle is operated between speeds of 0 – 33 mph.  Emissions are collected as the vehicle is driven.  If a vehicle does not pass the emission test during the first testing cycle, a second-chance test is automatically given. When the test is completed, the lane inspector exits the vehicle.  (NOTE: During the second step, a well-maintained vehicle may be able to “fast pass” after the first 30 seconds of the emissions test.)

During the third step, the motorist returns to the vehicle. At this time, the inspector returns the motorist’s registration information and presents the vehicle emission test results.

For model year vehicles 1976 – 1980, the three testing steps are similar except that these vehicles will not be tested on the dynamometer.  The vehicle emissions are checked while the vehicle is idling.  The inspector inserts a probe into the vehicle’s tailpipe, which collects the emissions for measurement.

For model year 1996 and newer vehicles, an Second Generation On-Board Diagnostics (OBDII) system test is performed.  This test does not require the vehicle to be driven on the dynamometer.  A scan tool is plugged into the vehicle’s OBD connector, which reads the vehicle’s computer to check the status of the OBD system.

Q. What if my vehicle fails the emissions test?

A. The lane inspector will provide the motorist with the Vehicle Inspection Report that states that the vehicle has failed.  The inspector will also provide additional materials that provide information on how to get your vehicle repaired.  More information is available at the customer service entrance of the Clean Air Car Check station or by calling the toll-free hotline at 888-240-1684.

Q. Where should I take my vehicle for repairs?

A. Any repair facility may repair your vehicle’s emission system. However, in order to qualify for a waiver should that be necessary, the repairs must have been completed by an Indiana Certified Emission Repair Technician (ICERT) Facility.  A list of ICERT shops will be provided to you before you leave the test site if your vehicle fails. 

Before choosing a shop, informed customers should ask:

• Do you have a gas emissions analyzer that is in good working order?
• Do you guarantee your repair work?
• Do you have a refund policy for guaranteed work?

If you have any other questions, please call the Clean Air Car Check toll-free hotline at 888-240-1684.