heat problem

[Corey]

hey guys ive had this same problem since ive bought the car, its never really been a problem because i dont winter drive the car but its just boggling my mind. so every year around winter time before i put it away and it is getting colder out i dont have heat, but it seems like once it gets cold enough outside out of the blue i get heat!? i have coolant in the car and there is no air in the system tried that already, it wouldnt be the thermostat because the heat either wouldnt work at all or the car would over-heat which it doesnt. but every yeard once we hit like 5 degrees out she heats up nice, but until then i dont have the heat. what is going on? lol

[pmurr181]

I had similar symptoms on my car when my
Water pump was going.

[Voodoo_ChildR32]

Waterpump, or clogged heater core, or faulty blend door. My old 89 GTST had no heat, flushed the system out and got heat. With my 91 GTS4, after installing a replacement turbo I had no heat, had to bleed it 3 times before I got rid of the airlock. Skylines are a pig when it comes to airlocks, it may take multiple bleeds to get all the air out. Did you use the bleed screw on the intake plenum or just leave the rad cap off? When you do it make sure your heater is cranked to full heat and with the engine running rev it up to about 2000-2500rpm, hold for a minute or so the let off the throttle, you should see air bubbles coming out the rad stem, repeat the process as many times as required until you have constant heat coming out of the vents at idle.

[Nismo_line]

my heat would work on and off. try hitting the dash above the glove box when you have the heat on full blast. if the heat starts working when you hit it then its your fan blower motor

[beacher1B0]

What about the interior temp sensor? Ive read multiple times people having trouble with temperature, solution turning out to be interior temp sensor or whatever its called.
Have you tried a Climate Control system self diagnostic?

[clone]

want to trade..
my heat is always on..the dash has been tampered with. I have been told maby the previouse owner forgot to plug vent wiring in.

[MKIV]

Similar issue on my end, except my heat will only come out from the window defrost and it takes forever for the heat to get hot. (And it's not even hot enough)

[cschepp]

Simple fix, take the dash off and Chaco everything out. My dash only took me 1hour to install and uninstall. Vents could be plugged or jammed. Also I would check alll the wiring to make sure everything looks proper and then look back to the actual unit for possible mal function