Engine heats up but takes a long time for warm air to blow. Once working, the thermostat works fine. Sometimes, warm air starts to blow and then goes cooler.

heater blows cold air idle chrysler 300 Questions & Answers ...

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Find solutions to your heater blows cold air idle chrysler 300 question. ... blow warmair for a few mins then back to luke warm. i replaced thermostat ... HEAT BLOWSCOLD AIR WHEN IDLING ONLY GETS HOT WHEN START DRIVING ... About 15 minutes after driving the diver side vents start blowing straight cold air but the ...

Heater only works when pressing the gas? - DoItYourself.com ...

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Nov 3, 2011 - When I press the gas, the air from the vents is nice and hot. .... So am Idriving a car with a ton of problems, or could the power steering ... Just anotherquestion, when warmed up does the engine temperature ... When the heater is on and I'm not pressing the gas pedal, luke warm air blows from the vents.

Heater blows cool air when stopped and warm air while ...

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RedditFeb 12, 2014 - Heater blows cool air when stopped and warm air while driving 2008 Kia Spectra (self. ... just fine but appears to blow cool air when I was stopped at a stoplight. ... My temp gauge would also be pegged high when at idle / low RPM. ...thermostat only blocks coolant going to the radiator, and the heater core, ...Missing: 300m ‎luke

Why is My Car AC Blowing Hot Air? - BlueDevil Products

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after changing thermostat was system bled correctly. also check relay and fuses, as well as door actuator under dash that allows door to swing from heat to a.c. sometimes switch goes bad, also make sure a.c. compressor isn't continuously running, some cars do but most do not. last but not least check to see if heater core is clogged hope this helps thanx

There may not be enough coolant in the system. What happends is the heating core is nothing more than a small radiator inside the car. If the fluid is low the heating core is empty. But once you start driving the water pump works harder and fills it up. Another possible cause is a sticking thermostat. If its stuck open the engine cant retain water to heat it up. Thus blowing cold air. Whith the engine cold remove the radiator cap and check your coolant level. If it is full a replacement thermostat may be needed. HTH and dont forget to rate.

1st thing I would do is have your thermostat checked at a rebutable rad shop also somtimes the rad cores get blocked and will not circulate the heat properly either problem can be rectified at the rad shop...good luck

replaced the thermostat and refilled coolant. so far so good.

Did you open the radiator cap and make sure the radiator is full of coolant? Sometimes the hose from the coolant reservoir to the radiator becomes plugged, and the radiator will become low on coolant even when the plastic reservoir is full. Low water levels will prevent the coolant system from getting hot water from the engine to the radiator or heater cores. This will cause the engine to run hotter while the heater appears to not be working.

this doesnt sound like a thermostat problem, rather a restricted heater core.
The thermostat housing, however, is a cheap cross-your-fingers-fix, and can be located by tracing the upper radiator hose back to the engine. The housing the hose is clamped to is where the thermostat is located. Remove 2 bolts, and replace thermostat.

You probably have a bad thermostat - the one that controls water flow to the radiator. It's supposed to stay closed until the engine reaches proper operating temperature. But when they fail, it's usually in the open position so the water circulate to the radiator all the time. The engine takes longer to warm up, and you shiver in the meantime. It does eventually get hot - it just takes a lot longer. I bet if you replace that thermostat you'll be toasty in no time. As for the cigarette lighter, your portable heater may have blown the fuse.

if you had heat before the problem than there is probably air still in the system . dont know your motor set-up , but it might have a bleed valve on the thermostat housing or a bypass line . if not , start the car and let it warm up ......in the mean time take the upper radiator hose off @ the radiator . When it heats up to normal temp , the coolant should flow out of the hose . that will tell you that the thermostat is opening , and it will also get the air out of the system @ the same time . As soon as it starts to flow , hook the hose back up and tighten . refill the cooling system back to the full line , than check for heat
GM is bad about getting air trapped in the system .

With the car warmed up,feel the heater hoses,are they both warm/hot near the firewall in the engine compartment?If they are both warm/hot,then the heater core should have circulation through it and it may be a "blend door" issue in the heater a/c assembly.If they are not warm/hot then the heater core could be dirty and plugged up and needs to be flushed.
If the above does not help,a drain and vacuum of the cooling system and vacuum refill will remove any trapped air.
Sometimes,clamping off the top rad hose and holding the engine rpm at 2000 rpm will force trapped air out of the heater core.(Watch temp gauge when trying this)
Lastly,a NEW thermostat doesn't mean its working correctly.