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1998 Dodge Dakota Question: I have poor to no heat in my truck I had heater core and radiator flushed

 

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sunny101871, Lewistown, PA, January 24, 2014, 17:47
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it did not work then I put a new thermostat still poor to no heat what am I over looking
also I did make sure all air was out when I filled radiator with fluids

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  • Answer #1

    G. T. Service Center (3079 Answers) , Stephenville, TX - (254) 638-3236
    ProfessorG January 24, 2014, 17:52
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    Did you check your heater hoses at the heater core, and are the both hot at operating temperature, I mean one is just as hot as the other and heat is the same as your upper radiator hose, and you know how hot that gets. Just checking first.

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    sunny101871, January 24, 2014, 18:17
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    top radiator hose is hot heater hose on driver side is hotter then hose on passenger side
    o I forgot to menschen that when I am at running temp and siting still I have heat when I am driving down the road it is cool

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    ProfessorG, January 24, 2014, 18:25
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    May I ask what temperature thermostat did you install? Either the thermostat is staying open while driving, allowing the coolant to cool when driving, or the heater core is restricted not allowing enough coolant to flow through it, or last but not least, the water pump impeller is not moving the water good enough to keep the coolant flowing through the heater core and the cold air going through the core is cooling the core faster then the heater can warm the cold air.

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    sunny101871, January 24, 2014, 18:44
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    sorry I put a 195

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    ProfessorG, January 24, 2014, 18:47
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    That should be good. Does your temp gauge stay around 200 deg or go lower while driving.

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    sunny101871, January 24, 2014, 18:48
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    it stays 195 and 200

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    ProfessorG, January 24, 2014, 18:51
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    Then you have a flow problem. Probably heater core restriction. Check your vacuum hose at the firewall to engine as well.

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    sunny101871, January 24, 2014, 18:55
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    what vac line and were would i look
    and heater core was done by a radiator shop

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    ProfessorG, January 24, 2014, 19:03
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    I believe dodge had some vacuum control in '99.you said the left hose was cooler than the right hose. It should be very close to the same temp and makes sense that it is warm at idle and not at highway speed. After flushing engine block some particles could have circulated into the heater core causing it to restrict again.

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  • Medium-star Best Answer
    pushrod January 24, 2014, 19:03
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    Try another thermostat. If you have heat stopped then you should heat going down the road IF the t-stat is working right! Sounds like ram air through the rad is cooling the engine down at road speed.

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    ProfessorG, January 24, 2014, 19:05
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    He said it stays around 200.

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    pushrod, January 24, 2014, 19:05
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    SO? Explain it another way!

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    ProfessorG, January 24, 2014, 19:06
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    Gauge could be wrong

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    pushrod, January 24, 2014, 19:07
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    Exactly!

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    sunny101871, January 24, 2014, 19:09
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    at stop light at idle I get heat if I am driving 55 down the road it is cool air

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    pushrod, January 24, 2014, 19:11
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    Heater box problem, vented outside air mixing with heated air! Only other explaination.

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    ProfessorG, January 24, 2014, 19:12
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    That's what we're talking about.

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    sunny101871, January 24, 2014, 19:13
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    how can get to it from the out side

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    pushrod, January 24, 2014, 19:14
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    Dont see that post, maybe i missed it. Dont you have a vent setting???

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    ProfessorG, January 24, 2014, 19:17
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    I was talking about thermostat.

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    sunny101871, January 24, 2014, 19:18
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    they side air box from out side were do I look and how do I get to it from out side
    to Professor G I tested t-stat by putting in boiling water

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    ProfessorG, January 26, 2014, 06:51
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    It needs to open and close while maintaining constant temp regulated. It still think the heater core is not getting good coolant flow. When it's warmer outside temp it will probably feel warmer in the cab but when the temp is colder it takes higher heat to warm the colder air. Same as sitting still verses driving down the road and forcing a higher volume of air. The core is not getting hot enough.

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    sunny101871, January 27, 2014, 03:10
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    i am not sure i understand even if it is -6 or 30 deg if i am seating still i have warm or hot heat if i am going down the road it gets cold.

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    ProfessorG, January 27, 2014, 08:23
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    I suppose at this point it needs to be seen by some who knows heater systems so they might be able to test it for you. If I had it here at the shop I could test it for myself and find your problem. Apparently your not understanding is not helping you find this issue.

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  • Answer #3

    ziptie12 January 26, 2014, 06:09
     Master

    To add to other questions....SPECIFICALLY ..what MODE setting are you using? Defrost , heat, floor , dash vents, combo of either? Is yours equipped with a setting for 'fresh' or 're-circulate' Heater control valve /blend door issue? Truck has A/C , right?.............just some more random thoughts ...hope it triggers something....I know I hate being cold on my commute!

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    sunny101871, January 26, 2014, 21:41
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    1 it dose no mater what setting am on it is hot when i am seating and cool when going down the road.
    2 i do not have a switch or button for a fresh or re-circulate air.
    3 yes my truck has ac

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    ziptie12, January 28, 2014, 21:51
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    blend door or fresh/recirculate door problem.If you're not familiar with heater controls inside vehicle, find someone (shop?) that is.

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