IL Air Team

Illinois Emissions Test Requirements [2026]

Illinois has no statewide safety inspection. But if you live in the Chicago metro area or Metro East (the seven-county St. Louis region), you need an emissions test every two years through the Illinois Air Team program. The test is free at official stations.

Cost: Free at Air Team station Frequency: Every 2 years Program: Illinois EPA Air Team
Heads Up

Rules change. Verify the current Illinois requirements with the state DMV or environmental agency before you go. This guide reflects the program as of 2026.

🔍 What Gets Inspected in Illinois

ItemWhat the Inspector Checks
OBD-II scan (1996+ gas)Check engine light status, codes, readiness monitors. Primary test.
Gas cap pressure checkMost vehicles get an evaporative gas cap test.
Visual smoke checkVisible smoke from exhaust or crankcase is a fail.
Diesel testingDiesel-powered vehicles 1997 and newer also tested.
VIN verificationInspector confirms VIN matches registration.
No safety checkIllinois does not test brakes, tires, lights, or other safety equipment.

📊 What Fails Most Often in Illinois

56%
#1 - Most Likely
Check engine light on

Check engine light on is one of the top reasons cars fail in this state.

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30%
#2 - Very Likely
Readiness monitors not ready

Readiness monitors not ready is one of the top reasons cars fail in this state.

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24%
#3 - Common
EVAP code (P0440/P0455/P0456)

EVAP code (P0440/P0455/P0456) is one of the top reasons cars fail in this state.

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22%
#4 - Also Check
Failed catalytic converter

Failed catalytic converter is one of the top reasons cars fail in this state.

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14%
#5 - Possible
Bad gas cap

Bad gas cap is one of the top reasons cars fail in this state.

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8%
#6 - Less Common
Tampered emissions equipment

Tampered emissions equipment is one of the top reasons cars fail in this state.

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🛠️ How To Prepare for Your Illinois Inspection

  1. 1. Make sure no check engine light is on - that is the #1 fail reason.
  2. 2. Test cap by listening for three clicks when tightening.
  3. 3. If you cleared codes recently, drive 100+ miles of mixed driving before retesting.
  4. 4. Vehicles 4 model years old or newer are exempt - no need to test.
  5. 5. No need to prep brakes, lights, or tires - they are not checked.

🧾 Not Sure What Will Fail Your Illinois Inspection?

Tell us your codes, symptoms, and car - our AI tells you the most likely cause and what a fix should cost before you hand the keys to an inspector.

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💬 Common Questions

Which areas of Illinois require emissions testing?

The Chicago metro area (Cook, DuPage, Lake, Kane, McHenry, Will, parts of Kendall) and the Metro East/St. Louis area (Madison, Monroe, St. Clair counties).

How much does the Illinois emissions test cost?

Free at official Air Team stations. You pay nothing for the test.

How often is the Illinois emissions test required?

Every two years, starting when the vehicle is 4 model years old. Newer cars are exempt.

What if I fail the Illinois emissions test?

You have until the end of the next month to repair and retest. Free retests until you pass. A repair waiver may be available if you have spent $450+ trying to fix it.

Are electric vehicles exempt in Illinois?

Yes, battery EVs are exempt. Hybrids with a gas engine are tested like gas cars.

Does Illinois have a safety inspection?

No, there is no statewide safety inspection program for personal vehicles in Illinois.

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