The heater on my 2000 Camry only blows warm air unless the engine is revving. Could this be a faulty thermostat (I just had the heater core replaced)?

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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Most cars today do not have a water diversion valve for the heater core; rather they use a blend door in the ducting under the dash. There are a pair of them. One door diverts input air either through the heater core or the A/C evaporator, or both. This will control temperature. The other door diverts air to the floor vents, dash vents, or the defroster vents. These doors are vacuum-controlled on most models. You could have a door problem, or possibly a clogged heater core. To check the heater core, run the vehicle to operating temperature, and then trace the heater hoses to where they enter the firewall. Check each hose for temperature. The inlet hose should be very warm to the touch, and the outlet one the same or slightly cooler. If the outlet hose is much cooler than the input, there is probably a restriction in the heater core.

Most likely the thermostat broke. I expect that you have an older Hyundai and never had the anti-freeze changed. When the engine is cold the thermostat is closed which causes the engine to warm up more quickly. A warm engine runs more efficiently (less gas) and more smoothly. When the engine temp reaches a certain temp the thermostat opens and then allows the hot engine coolant to run through the lines to the heater core. The heater blows air over the heater core which produces the warm air that warms up the cabin. Thermostats used to be cheap and easy to change. I would suggest a web search for how to replace the thermostat. Something like 'hyundai accent 2002 replace thermostat".

Time to either flush or replace the heater core as it may be plugged with rust build-up. I'm assuming the engine is running at normal operating temperature, if not then the thermostat may need replaced.

low fluid level or heater control valve may need replace..check hoses going to heater core...if cold...between heater control valve and heater core..replace control valve

Thermostat.? if you haven't? Do it first then try it. While the car is running for a while touch the heater hoses that lead to the firewall. if one is cold and one is hot? You have a blocked Heater core. Follow the hoses back to the engine. Unconnect them both. By using a garden hose flush out the heater core do one side and then reverse by doing the other hose Lots of junk will come out so be care ful. Mistake people make is "Flushing the system" That doesn't mean your flushing the heater core.
Seeing that you have done everything else it could be the thermostat which you didn't list or the heater core being clogged. When you finished installing the thermostat and flushing the heater core out. Replenish the coolant system . If you have a bleeder on the thermostat housing? use it . loosen it and top off the fluid until you see fluid comeout of the bleeder. The system being air bound would cause no heat..

how are you looking at your thermostat with the car running its not possible unless you have xray vision check you water level cars have to warm up for you to get warm or hot air

it could be the cold air blend door or the thermostat is the engine temp up to the middle of the gauge or close to it if so then thermostat is ok if not then go ahead and replace it.

faulty thermostat will cause overcooling by staying open at all times.to check this.crank up vechicle until it warm up.becareful watch out for drivebbelt and cooling fan.feel all hoses.plus heater core hoses all hoses should be hot when engine warm up.if engine run until it get hot all hoses feel luke warm thermostat is bad. if all hoses get hot.check your fuses to HVAC mode switch.if all is good.you have a faulty heater air door or it could be stuck.your heater cores could be restricted stopped up.if you have climate control this is a dealership fix.

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.