Rep Power: 0

when i turn the hot heat on its still blow the cold air ....??!!
does anyone have same problem ???
what is it ...and how can i fix it ..??

 
Rep Power: 278

So even if you keep it on for even an hour, you get cold air?

 
Rep Power: 319

Well, first make sure the car is warm. The heat comes from the engine coolant, so if the temp gauge on your car isn't up, you don't have heat. Then check the coolant level to make sure you have coolant.

If that is not the case, then you have one of 2 things wrong. 1. heater valve is bad, it is a small valve that alows the coolant to flow through the heat exchanger that make the air hot (also called the heater core). This goes bad and you can block all the coolant to the core. 2. The heater core itself is blocked. Neither of these are fun or easy to fix.

 
Rep Power: 258

Or it could be the very simple and often overlooked thermostat. If its stuck closed wouldnt it prevent hot coolant from running through the heater core?

 
Rep Power: 453

after the car warms up, if it does, turn the heat on full blast and fell the heater hose going to the heater core and the one coming from it. if neither feel warm or feel full, you have a heater valve issue or dash control issue. if it feels warm going in but not coming out, the heater core is clogged. also put your ear up to the dash control and as you rotote the **** from cold to hot, see if you can hear the dash controls move.

What you can also do is check to see if you have any HVAC trouble codes. I have the procedure to check for those, but not with me, maybe someone can come on and give them to you. they are different then the OBD truble codes, they are for the cars HVAC system. this will see if you have any dash control or motor problems.

 
Rep Power: 319

It could be, but then the car would overheat, in which case the last of his worries are if the heater is working. The alternative is that it is stuck open, in which case the car is always cold. This could happen, and I've had it happen, then the coolant never gets warm enough to produce warm air. Either of these can be figured out normally by just watching the temperature guage, or as said above by feeling the hoses.

 
Rep Power: 0

My car has just started having a similar problem. After the car gets warm and I've been driving down a few blocks it blows warm air. When I sit for a period of time (e.g. long stop light) the air gets really cold until the engine RPMs get up, which then it blows warm air again. I'll have to check my coolant level but I really think its something mechanical because I just noticed it started like a couple days ago. I've got 105k miles on it and am planning on doing the waterpump and timing belt very soon. Could it possibly be the waterpump going out? I've let it idle for like 15-20 mins to get warm in the snow and the temp gauge got to a point and seemed to stop, so I assume the coolant is circulating.

EDIT: I just got thinking, this whole winter it has taken longer for my car to get warm. Maybe the thermostat has been corroded and stuck open, and now its won't open til I rev the engine up. My radiator was replaced about 1 year and a half ago and the body shop probably put crap coolant/water in it.