I've got an interesting situation. While in the jeep and moving forward, there is a not so pleasant breeze coming in from under the dash. When the temps are very low it is uncomfortable, no matter how high or hot the heater is! At first I thought that it must be one of the rubber grommets, but that wasn't the case. The firewall and all grommets appear to be in good condition. Could the air intake for the heater be cracked or broken?
Thanks, Doug