SERVICE INFORMATION After ECM reprogramming, the Calibration Verification Number (CVN) needs to be automatically calculated prior to State emissions testing (also known as Inspection Maintainence, I/M, or SMOG testing depending upon location). Allowing the vehicle to idle for 22 minutes will allow for faster CVN calculation. It is recommended that customers utilize this method if the vehicle needs to be tested for emissions soon after ECM reprogramming. See this bulletin for further detail.
