42550 - CUSTOMER SATISFACTION. CERTAIN VEHICLES, EQUIPPED WITH 6.0L CNG ENGINE (RPO LC8) AND DEDICATED CNG VEHICLE FUEL (RPO FHZ), MAY HAVE A CONDITION IN WHICH THE ENGINE STALLS AT THE END OF AN AGGRESSIVE DECELERATION EVENT OR ENGINE IDLE DROPS BELOW DESIRED RPM AFTER DECELERATION. IF THE ENGINE STALLS, THE OPERATOR WILL HAVE TO SHIFT TO PARK OR NEUTRAL TO RESTART THE ENGINE. DEALERS WILL REPROGRAM THE ENGINE CONTROL MODULE (ECM) AND TRANSMISSION CONTROL MODULE (TCM).