WHEN THE ENGINE IS STARTED FOR THE FIRST TIME AFTER PARKING THE VEHICLE OVERNIGHT IN COLD CONDITIONS (BELOW 32 DEGREES FAHRENHEIT / 0 DEGREES CELSIUS), SOME VEHICLES MAY EXHIBIT A ROUGH IDLE AND/OR THE CHECK ENGINE LIGHT ON WITH ANY OF THE FOLLOWING DTC(S) STORED IN MEMORY.•P0300 - RANDOM MISFIRE DETECTED•P0301 - CYLINDER NO.1 MISFIRE DETECTED•P0302 - CYLINDER NO.2 MISFIRE DETECTED •P0303 - CYLINDER NO.3 MISFIRE DETECTED •P0304 - CYLINDER NO.4 MISFIRE DETECTED THIS MAY BE CAUSED BY FROZEN WATER ACCUMULATED IN THE MAIN SILENCER, RESTRICTING EXHAUST FLOW.