Nissan Repair Questions? Ask a Mechanic for Answers ASAP
If water is circulating in the system and the top hose is hot, are you sure the thermostat is not in backwards? Because if it was stuck open the upper hose would not be getting hot.
Please forgive me that response was for another question,
On your nissan it sounds like your auxiliary water pump has failed, quite common actually, and you describe its systems perfectly, this pump is small and mounted in the heater core hoses, can you locate it? With truck running and heater on it should be running, if not check power and ground
Yes that is the pump I am referring to. And yes u need to check its operation. because of the design of the case and heater core it is
Possible an air pocket will get in heater core and prevent that side from drawing hot air. We will even elevate the vehicle front up to get the air out, and that pumps operation is critical. Another common problem is the in car temp sensor its located about where your right knee is (driver) and it can become unplugged. Drop the drivers kick panel and check. It looks like a little speaker grille, if not park the vehicle at a steep incline with front up see if heat improves if it does u have air in system
Yes, have you parked on an incline and checked it's effect on the heater
Both actually, elevating it will help with the bleeding, refer to the coplant bleeding procedure. And perform it with the truck elevated. Let me know what you find