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Types of Vehicle Testing

On-Board Diagnostic (OBD)

Pre-Conditioned Two-Speed Idle (PCTSI)

The Pre-Condition Two-Speed Idle (PCTSI) Test is designed for 2007 and older non-diesel vehicles with the GVWR of 8,501 LBS to 10,000 LBS. The PCTSI measures tailpipe emissions (hydrocarbons/carbon monoxide) at cruise engine speed and then at an idle speed. In addition to this test, all vehicles are subject to the visual verification of the catalytic converter; if one or more catalytic converters are missing from your vehicle, the emissions test will fail.

Gas Cap Pressure Leak Test

The Gas Cap Pressure Leak Test is required on vehicles that receive the Pre-Condition Two-Speed Idle (PCTSI) test. This test ensures the gas cap(s) on your vehicle are capable of properly sealing the gas tank, which allows the vehicle’s evaporative emission system to properly dispose of fuel vapors. Note, if your vehicle requires the PCTSI test and the gas cap(s) are missing from your vehicle, it will be rejected from emissions testing. Malfunctioning gas caps will also cause your vehicle to fail the emissions test.

Modified Snap Acceleration (MSA) Test

The Modified Snap Acceleration (MSA) test is for older diesel-powered vehicles. The emissions analyzer will utilize an opacity meter to measure the density of smoke emitted from the vehicle's tailpipe.

Vehicles subject to the Modified Snap Acceleration (MSA) include:

  • 2006 and older diesel-powered vehicles with the GVWR between 8,501 pounds to 10,000 pounds.
  • All 1996 diesel-powered vehicles with the GVWR up to 10,000 pounds.

Please note that NOT all Test Centers can accommodate this emissions test. Please contact the motorist hotline at (877) 469-2884 or click here to find the closest Full-Service Test Center.

In addition to this test, all vehicles are subject to the visual verification of the catalytic converter; if one or more catalytic converters are missing from your vehicle, the emissions test will fail.