Welcome to the Connecticut Emissions Program

Depending on the vehicle model year, make, fuel type and driveline configuration your vehicle can receive one or more of the following tests:

On-Board Diagnostic (OBD)
Accelerated Simulation Mode 25/25 (ASM)
Pre-Condition Two-speed Idle (PC TSI)
Load Mode Diesel (LMD) or Modified Snap Acceleration (MSA)
Gas Cap Pressure Leak Test

The Test Center Manager at your test center can explain the differences and how the tests are administered. More detailed information regarding the different tests can be found under the Test Procedures tab.