Heat in the car when it drive .. not when I stop?

Question

I have a 2005 Nissan sentra and i just replaced the thermostate and I only have heat when I am driving. i can let it warm up forever and it doesnt get heat and defrost i i begin to drive. i also have a new raditor.

Answer 1

Either you have some really good coolant or a really faulty thermostat. You only get heat when the coolant is flowing through the system (and through the heater core, a small "radiator" in the dash). Either the car just isn't heating up or the thermostat doesn't think it has and isn't letting the coolant flow.

Answer 2

There's an air bubble in the system. Driving speeds up the rotation of the water pump and forced a little bit of circulation of the hot coolant.

You need to properly bleed all the air from your system, there are a few screws (properly called bleeder valves) that you loosen up and let the hot steam out until liquid starts coming.

You probably need a Haynes manual from your library to point them out to you, or if a mechanic did this job, take it back and tell him there's air in the system.

Answer 3

I have a 2003 nissan 350z and it does the same thing. I got the coolant system flushed and it worked. The thermostat is not bad because if it was, your car would probably overheat, and your coolant pump is not bad because again, your car would overheat. Air accumulates in the heater core.

Answer 4

not sure...I had this problem with my jeep and it was because the coolant was low. Turns out I had a leaking radiator and a blown head gasket and my antifreeze was leaking into the cylinders. Call a shop and tell them your problem...they might have a few ideas of what could possibly be wrong....good luck!

Answer 5

maybe the heat pump isn't closing all the way or you have air in it. Have them check it.

Answer 6

water pump & fan stopped