My 2001 RX300 heater will not blow warm air, no matter where the temp is set. It blows air, all right, but it's cold as can be. It has coolant, and the engine temps are running normal. Any suggestions?

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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thermostat or low coolant

where did you buy your thermostat? if you bought a fail-safe style thermostat it could have been no good before you even put it in. also is your tempeture gauge coming up to operating temp?? if it isnt your thermostat may be stuck in the open position allowing the coolant to circulate freely and not actually warm up. i would also check the lines going into the heater core. if one line is hot and the other line is cold than your heater core is probably in need of a flush or replacement.

the heater blowing cold at an Idle and warm while driving it,is usually low coolant in the radiator,remove the radiator cap when engine is cold,fill to the top,and fill overflow tank to full,if that doesn't take care of it,check the heater hoses at an idle and see if they are both the same temp,it might be a water pump not doing its job.

I'm no 'expert' but it sounds like possibly 2 different problems. Your heat comes from warm/hot coolant circulating through the heater core, and the fan blowing air through/over it. If your thermostat is not opening the coolant won't circulate. Thermostat is a not too difficult or costly starting place. No air flow leads me to think you have a blower motor issue, perhaps start with the fuse. Hope this helps.

No ductwork [to the lower vents] under the dash. They are part of the heater core / blower housing is integrated (all one piece).

After reviewing shop manual, we suspect that one of the three damper flaps is not positioning correctly; or debris has blocked one side (which makes more sense given the symptoms).

We're waiting for the temperatures to get back in the plus numbers to check out the physical arrangement.

Its just a vent damper plate not operating, it's like a gate which controls the flow of air,,usually they are operated by vacuum, or cables.
Service center time, unless you are handy with your own repairs.

did you check the fluid level by removing the rad. cap? Radiator should be full to top. If Chryslers are low on coolant, the heater will not blow warm air.

I had the same problem with the heater only working when accellerating. Found the overflow tank pick up tube was kinked. This of course made my coolant level low. So when the cars hot the coolant would push into the overflow, but when the car cooled the kink would prevent it from flowing back to the radiator.

Check your coolant level sounds like it might be low.