At a loss of what to do next. My whirlpool gold refrigerator freezer is working great. 0-5 degrees. My fridge won't get down past 45 on max cold setting. I've taken off the freezer panels. The defrost is working properly, the return air from the fridge is not obstructed/frozen. Condenser fan and evap fan is working. This model doesn't have any sort of flapper door on the return or supply air to the fridge section. The panels are all installed properly. Yet, when the freezer door is closed air flow to the fridge is 1/2 of what it is with the door open. The air that does make it into the fridge I measured at 30 degrees maybe a little colder, but there is hardly any air pressure flowing into it. No odd noises. The panel is installed at rear of unit so airflow is pulled over the condenser. I unhooked the diffuser and manually pushed it either direction and airflow did not increase. All seals are in place on the freezer panels.