Hey ya'll ,posted a couple weeks ago rear air much colder than front air. Finally figured it out, all the actuators were working, plenty of R-134a, but the magic answer is, the valve that stops hot water from going to the heater core isnt working. It is vacuum controled, getting no suction if I cant get it to suck Im putting a manual valve in. Hope this helps anyone having the same issue. Later, God Bless