I just bought a 2000 WJ Limited with a 4.7 so wierd HVAC problems have crept up heat is completely inop the dual zone climate doesnt work always blows cold no matter what temp you have it on. Now the ac blows hot while it setting still but get a little cool driving down the highway I thought I was low on refrigerant so I add some no change. The electric fan and mech fan is running. I have a couple ideas what are yours? Any help is appreciated!!