low coolant
02-15-2010, 04:50 PM
#31
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WHAT is "it"? WHAT are you touching? The actual heater core or the box it sits in?
The low coolant light will not come on when the sensor is unplugged.
When the heater core (or whatever you are touching) gets cool, is the AC on or isn't it? Does it matter if the AC is on? It sounds like the heater core is OK, but the AC is on, resulting in cool (but not cold) air flowing through the heater BOX (not the core).
You still have not answered Rob's question about whether you made sure the heater core was not plugged. You can't "see" a clog in the heater core - you have to blow air through it, or flow water through it. You have to answer the questions, if you want help.
The low coolant light will not come on when the sensor is unplugged.
When the heater core (or whatever you are touching) gets cool, is the AC on or isn't it? Does it matter if the AC is on? It sounds like the heater core is OK, but the AC is on, resulting in cool (but not cold) air flowing through the heater BOX (not the core).
You still have not answered Rob's question about whether you made sure the heater core was not plugged. You can't "see" a clog in the heater core - you have to blow air through it, or flow water through it. You have to answer the questions, if you want help.
02-15-2010, 06:52 PM
#32
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Im really Sorry guys i'm just as confused as you guys are. Yes i checked the door flap it seems to be working. About the heater core i still have the dash apart and when i touch it when the heater is not on it is hot but as soon as the heater turns on it gets cool. when i took the heater core out i didnt see anything that was blocking it. The coolant sensor is not coming on after disconnecting it and i have been trying both the air conditioning and defroster and they are still blowing out cool air it isnt cold but its barley warm. If im sitting at a stop light or driving around at low speeds the car starts to get up to about 210 but even if sitting the fans come on and it goes back down. Im going to be doing a tune up tomorrow and i have a lifetime warranty on the water pump so would it be wise to take it off and just change it? see if that fixes the issue
02-15-2010, 06:57 PM
#33
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idk-but this is only a suggestion-is it possible for you to procure (borrow, purchase, etc.) a laser thermometer? this would really help in locating coolant flow problems, heat exchange from the core-actual temp of the coolant into the core, actual temp of the core, actual temp of the coolant out of the core-you get my diagnostic take on this? laser thermometers are fairly inexpensive nowadays and can be used for trouble shooting many other automotive problems. it probably will help you start to narrow this problem down.
02-16-2010, 11:10 AM
#34
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The light is off after just unhooking the sensor but the heater still is not working. It completely stopped working and the the control switch seems to be working just fine. Could it be a clog in the radiator that just not getting coolant where it needs to be or the actual heater core. Also when i got the heater working last time the air was really humid and its not humid outside it also smelled like coolant a little bit
I think you mentioned in an earlier post that everything gets hot...the hoses and the heater core...until you turn the heater on. What does that mean, exactly? With the temperature **** in the warmest position, is everything hot? Does it cool off once you turn on the fan? I'm not busting your chops, I just don't exactly understand. Anyway, if things get hot it is working properly. I run a 160 thermostat and the air is just warm even though the flow is normal.....
Im sorry what i ment is that everything gets hot like hoses and everything. The heater core gets hot but as soon as you turn on the heater the heater core cools off idk if that is normal. The temp never gets past the first notch. The heater is on the hottest setting and its just not getting hot
With the heater temperature control **** ("J" in Shoebox's diagram, linked below) in the "high" position, but the heat/vent/AC selector switch ("36" in Shoebox's diagram) "off", the heater supply and return hoses and the heater core are hot to the touch. IS THIS CORRECT?
When you turn the heat/vent/AC selector dial to "heat", the heater core rapidly cools down. IS THIS CORRECT? And you have changed nothing else, except the position of the heat/vent/AC selector switch?
Given that the heat/vent/AC selector only moves the flapper doors, and given that you have the heater box disassembled to the point where you can reach in and touch the core, its very hard to understand why the core suddenly cools off. Nothing is changing, except the position of the flapper doors.
http://shbox.com/1/hvac_vacuum.gif
You do realize, that if you look at Shoebox's diagram, the air leaves the fan ("5"), flows through the AC evaporator core ("3"), and then through the heater core ("4"), depending on the position of the temperature control door ("6"). If the heat/vent/AC switch is in the defrost position, the air hitting the heater core will be cold, because the AC is running, depending on the position of the temperature control door ("6")?
This is the only reason I can think of that turning the heater on would cause the heater core to cool down. It can't be related to coolant flow through the heater, because there is nothing in the heater core coolant lines that changes when you turn the heater on.
Last edited by Injuneer; 02-16-2010 at 11:12 AM.
02-18-2010, 09:12 AM
#35
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Yeah thats all correct and i think i may have found it. The water pump is leaking. Im going to change that this weekend. Do you think that could be the problem?
Also thank you guys for your input and sorry for all of the confusion
Also thank you guys for your input and sorry for all of the confusion
02-18-2010, 09:15 AM
#36
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I have no idea what is causing the problem. Even with two degrees in mechanical engineering and more than 40 years work experience, it is beyond my comprehension how turning the selector **** could affect the temperature of the heater core, beyond the possible interaction with the AC.
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