Nissan Repair Questions? Ask a Mechanic for Answers ASAP
Was the heater valve not opening on its own?
are you there?
I understand that YOU opened it, but it's important to know why here.
If the water valve is NOT opening by itself when turning the heat on, then that means either the water valve is bad or the front air control is bad.
if the front air control is bad it could effect other things as well, like the blend doors for hot and cold airflow.
The ONLY thing that's gonna fix is a heat issue from a faulty heater valve.
which is USUALLY the fault with no heat, but it would be important to know the valve was bad before opening it manually.
Yes, thats the dials.
If the heater valve is open and you still cannot get heat (assuming the truck is heating up properly)
then either the heater core is blocked, or the blend doors are not functioning.
If the return hose leaving the heater core and coming out the firewall is not warm, then the heater core is blocked and you need to back flush it.
Did you check your coolant level? have you tried REVING the engine up and see if it produces heat when holding it reved??
by rulling out other things first.
you KNOW it's not the water valve, if reving don't work then you know its not an air pocket, check the coolant return hose and if its warm then the heater cor is not blocked, that would leave you with a blend door issue and it would likely be from the front air control is the heater valve was not opening either and it was good.