Welcome to the Connecticut Emissions Program

Why your vehicle specifically failed, depends on the model year, weight and driveline configuration of your vehicle.

If your vehicle is a 1996 or newer, gasoline-powered vehicle, or a 1997 diesel-powered vehicle, that has a Gross Vehicle Weight Rating (GVWR) that is less than 8500lbs, it may fail the On-board Diagnostic (OBD) Test for the following reasons:

+  Malfunction Indicator Lamp (MIL), also known as the “Check Engine Light”, is illuminated indicating an emissions-related malfunction.
+  The OBD system itself maybe inoperative;
+   The Diagnostic Link Connector (DLC) is damaged, inaccessible or missing; or
+ The catalytic converter is missing.

If your vehicle is a 1995 or older, and has a GVWR, that is less than 8500lbs, it may fail the Acceleration Simulation Mode (ASM) Test (this is a tailpipe test that simulates driving at 25 MPH using the dynamometer) for the following reasons:

+ Your vehicle is emitting excessive levels of one or all of the major air pollutants, such as hydrocarbons, carbon monoxide or nitrogen oxides;
+ Your vehicle’s gas cap is leaking, allowing excessive amounts of fuel vapors to escape into the atmosphere; or
+Your vehicle’s catalytic converter is missing.

If your vehicle is a 1995 or older, all-wheel drive vehicle, or limited by traction control, or a vehicle that has a GVWR that is over 8500lbs, it may fail the Two Speed Idle (TSI) Test (a tailpipe test with no drive mode simulation), for the following reasons:

+ Your vehicle is emitting excessive levels of one or both of the major air pollutants hydrocarbons and/or carbon monoxide;
+ Your vehicle’s gas cap is leaking, allowing excessive amounts of fuel vapors to escape into the atmosphere; or
+Your vehicle’s catalytic converter is missing.

If your vehicle is a 1996 or older diesel-powered, it may fail either the Loaded Mode Diesel (LMD) or Modified Snap Acceleration (MSA) opacity test for the following reason:

+ Your vehicle is emitting excessive levels of particulate matter (smoke).