SOME VEHICLES WITH 4.6L, OR 6.8L ENGINES MAY EXHIBIT A ROLLER FINGER FOLLOWER COMING OFF DURING ENGINE CRANKING IN COLD TEMPERATURES BELOW ZERO DEGREES F. A ONE-TIME NOISE FROM THE ENGINE MAY BE HEARD, FOLLOWED BY ROUGH RUNNING / MISSES, NO START, LACKS POWER AND A CHECK ENGINE LIGHT (MISFIRE DIAGNOSTIC TROUBLE CODES). *TT