Nissan Repair Questions? Ask a Mechanic for Answers ASAP
Hi There, I'm Clayso a certified master automobile technician with 30 years of automotive repair and diagnostic experience.
From your description most likely the coolant level is low and there is air in the system, unless the A/C compressor stays in gauged. When there is air in the cooling system it get trapped in the heater core and no heat can be felt at the vents. Follow this coolant fill procedure and see if you have heat.
Lower the coolant level and then raise the front of the vehicle about a foot. Slowly fill the vehicle with coolant. Run the engine and have the heater on full. Slowly fill the vehicle with coolant through a funnel attached to the radiator fill neck. Check temperature of the heater hose from the engine to the heater core. The water control valve should be open at 200-206 F. If the flow and temperature are good and the valve is opening, check the coolant flow thought the heater core. You may also want to flush the cooling system in case the heater core is stopped up. Make sure the coolant mixture used is no stronger than 50/50 water and antifreeze.
I hope this information is helpful. If you have any questions let me know. You can reply back to me through this thread at any time.
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