In my 2014 Enzo I have a factory installed heater. The fan works at all three speeds but only blows cold air. One of the things the dealer has asked me to do is hook up a garden hose to one heater hose and flow the water out the other heater hose (into the bilge) to check for kinks or blockage.
With the garden hose on full pressure there is only a 1/4 flow coming out the other end. Should the flow be greater than this?