I have an 01 ram 1500 5.2. It runs good in idle in park but when i try to drive it it will not run at any less than full throttle. It also backfires while its having the problem. Im stumped with this problem. I also noticed that this truck has the hottest exhaust gas ive ever felt. It feels like holding your hand in front of a heat gun. I dont know if the problem is related or not but im open to suggestions.