2001 Chevy Venture - My heat is not as hot as usual and blows cool when idle. Coolant level is fine. Temp Gauge isn't working.

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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Is the vehicle really over heating would be the first thing to address . If this vehicle was brought to the chevy dealership I work at , hooking up the factory scan tool to see what the PCM - engine computer is seeing for coolant temp . Too see if the cooling fans work , too see what temp info . the PCM is sending to the instrument cluster . I know GM had stepper motor problems in the instrument cluster . The step motor is what makes the temp , fuel , speedo , tach , gauges needles move . Just replaced a cluster in a 2005 chevy cavalier , temp. gauge goes full hot after just starting the vehicle . The cooling fans should kick on at around 223 degress , do the cooling fans come on ? Given the amount of electronics on these vehicles , it maybe best to take it to a qualified repair shop . That knows how to test these systems . Without testing I would only be guessing as to what could be wrong , Unless your prepaired to replace a bunch of parts , because your going to get a lot of different cause's from on here . Testing is the proper way to finding the problem . If you don't have a scan tool to view engine sensor data parameters , temp sensor. At harbor freight they sell a Non-Contact Infrared Thermometer With Laser Targeting. This will show what the temp is .
Non Contact Infrared Thermometer With Laser Targeting

Overheating Case Study Ford Explorer 4 0 SOHC Part1

Well that can be true but you can't be sure without running some tests.
Did you get the cap off ? Is the radiator full of coolant ?
Was the radiator fan running when it was showing hot on the gauge ?

For car running hot and overheating issues, I suggest to you go through this help links. Click this link below and go through the troubleshooting procedure to take care of the problems: ----Car runs hot? http://howtobyme.blogspot.com/2011/11/car-runs-hot-in-traffic.html
-----------All types of car overheating problems and troubleshooting?

http://technoanswers.blogspot.com/2011/11/all-types-of-car-overheating-problems.html
Car freeze overnight and started overheating while driving?http://technoanswers.blogspot.com/2012/01/car-freeze-overnight-and-started.html-----------Engine Overheats and heater blowing cold?

http://howtobyme.blogspot.com/2011/11/engine-overheats-and-heater-blowing.html

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Car overheats and Air blows hot at idle?
http://howtobyme.blogspot.com/2011/11/car-overheats-and-air-blows-hot-at-idle.html
--------overheating? http://schematicsdiagram.blogspot.com/2011/12/buick-century-overheating.html
----------Car engine Overheats and transmission starts slipping?http://schematicsdiagram.blogspot.com/2011/12/car-engine-overheats-and-transmission.html
----------This details will help.Thanks.

This is usually caused by air in the cooling system. While the engine is cool, check your fluid level in the coolant tank. Then check the radiator to make sure it is full. If both of them are full, the system has to be bled. To bleed the system, take the radiator cap off, start the engine. If there is air in the system it will bubble out and the fluid level will drop, add coolant until this stops.

YOU NEED BLEED COOLANT SYSTEM.CHECK COOLANT LEVEL IN RADIATOR.ADD MORE DEXCOOL UNTIL COOLANT LEVEL IS CLOSE TO RADIATOR SPOUT.CRANK ENGINE LET IDLE UNTIL TOP RADIATOR HOSE GET HOT.WATCH TEMPERATURE GAUGE.IF TEMPERATURE GAUGE START RISING TO HOT ZONE.TURN OFF ENGINE.LET COOL DOWN.USE LARGE RAG SLOWLY OPEN RADIATOR CAP A LITTLE AT A TIME UNTIL ALL PRESSURE RELIEVED.REMOVE RADIATOR CAP.ADD MORE COOLANT.CRANK CAR AGAIN LET IDLE UNTIL TOP RADIATOR GET HOT.KEEP EYE ON TEMP.GAUGE ALSO.WHEN TEMP.GAUGE STOP CLIMBING.YOUR COOLANT SYSTEM BLED.WHEN DONE LET CAR SET A WHILE CHECK COOLANT LEVEL.ALSO FIRST THING IN THE MORNING CHECK COOLANT LEVEL AGAIN.AND BESURE ADD COOLANT IN THE OVERFLOW JUG TO THE COLD MARK.DONT OVER FILL THE COOLANT RESERVOIR JUG.WORK SAFELY DONT GET SCALDED.

SOUND LIKE ENGINE RUNNING HOT.MAKE SURE COOLING FAN TURNING ON. WHILE ENGINE IDLING WATCH TEMP GAUGE AS THE TEMP CLIMB COOLING FAN SUPPOSE TO TURN ON IF NOT.CHECK FAN FUSE AND RELAY. IF BOTH GOOD HOT WIRE IT. NO RUN REPLACE FAN MOTOR IF FAN MOTOR DO RUN. YOU COULD HAVE A FAULTY COOLANT TEMPERATURE SENSOR OR SHORT IN FAN CONNECTOR OR WIRES. CHECK COOLANT LEVEL.MAKE SURE YOU HAVE 50/50 MIXTURE OF WATER AND ANTIFREEZE.TO BE ON SAFE SIDE REPLACE THERMOSTAT AND PRESSURE CAP.

Chevy made some weak intake gaskets on 3.1 and 3.4. My guess is that the intake gasket is weak and/or leaking and it is letting pressure out somewhere. At idle maybe the system pressure is to little to push hot coolant into the heater core.

Make sure you have gotten all the air out of the system by running the car with the cap off for a bit.. also make sure the radiator overflow if at proper level.. next look at your radiator and see if it is plugged up with trash bugs what ever this will slow your cooling big time.. also look between your radiator and your air condition condensor and make sure its clean also there can be trash in there causing it to heat .. also check belts make sure they are tight.. really sounds like you started with air in system and system might be air locked needing to run a bit with cap off when cool. dont take cap off when hot ... make sure over flow is full also... thanks and holler if you need more. Jerry

either the temp sensor is bad but, it sounds like the fan relay is stuck.
replace the relay its in the fuse box.