So I bought a 01 Dodge Durango with the 4.7 engine in it. It ran when I got it but wouldn't stay running in cold weather unless I stayed on the gas and waited for it to warm up. I got a p1391 code and a p0340 code for the camshaft or crankshaft. Well I replaced both now it won't run at all. Tried new sensors and nothing. It will fire up right away the rpms reach about 3grand and it stalls out. I took the spark plugs out and had a friend turn it over and flames were shooting out of the spark plug port. I'm out of ideas. Any suggestions would be great. Hopefully someone had this problem and managed to fix it.