'04 Chev Silverado 1/2ton Heater only blows warm air when motor is at high RPM. When I stop and its just idling, it blows cool air.

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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Sounds like air in the cooling system. Try taking radiator cap off and letting the vehicle run with heater on high. As bubbles come out add coolant. This may take 20 minutes to a half hour.

Check the heater core, if it's OK, check the thermostat again, but it could be the heat switch too.

Heater core may be clogged. Try flushing it to see if water flows through freely. Also check the heater water control valve for restrictions.

You might be low on freon if not compressor going bad to see if your compressor is going on and off turn on a/c on max have some one hold gas peddle down around 1500 rpm or just at a small fast idleif compressor goes on and off recharge it most likely one or two cans will be enough

check the heater hoses going from motor thru firewall to heater core / if they get warmer when motor is at 2000 rpms or higher then most likely problem is heater core stopped up / if the hoses dont change then thermostat could be stuck open ! good luck

u might be right but also check over the vacuum system for a leak often it is just lossing to much vacuum some where else.....hope it helps

You have an air pocket in the cooling system. To bled it out you will have to park vehicle on an incline or jack up the front end untill the radiator cap is higher than the heater core. The remove radiator cap and run engine until warm then hold rpm to about 1200 rpm's and top off coolant level until you have no more bubbles.

you should have hot water on all rad. hoses when the motor is running at a norm. temp. the water is not going through the heater core like it should. you have cutoff valve bad low water are a stopped heater.try a hoter thermostat if none of the above are true.

Hi!
Look like you may have an air lock.
Put the car on level ground, start it from cold with the coolant filler cap off, have plenty of warm/hot water available.
Leave to idle watch the coolant filler area but NOT TOO CLOSE, when at operating temp it may appear to boil over loads of bubbles, gurgling and some steam, top the coolant system up with the warm water wait until things settle then replace cap you may have to do this a couple of times.
Remember your anti freeze?
Good luck!
Paul 'W'
Onyer~EDson(:0) {#><U.K.