Question about GMC Sierra 1500

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1988 gmc truck heater stays on vent not going to defrost

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  • icet670 Nov 19, 2008

    Hi Emmisionwiz,



    Was able to repair problem. There is a position motor under the tape deck that would not turn...removed and cleaned...working good now.



  • yadayada
    yadayada May 11, 2010

    Do you have automatic climate control?

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  • 21,949 Answers

Wow a classic

Posted on Nov 06, 2008

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Heater Coil Leak


Hey mad40bx that will be your heater core,,just pick up a new one and grab a haynes or chilton manual for your truck if you are not familiar with the procedure its not that bad, if you dont need it fixed immediately take the 2 hoses off from the firewall (One is supply and one return) and couple them together this will bypass the heater core until you are ready to fix it, good luck

Nov 09, 2008 | 1988 GMC S-15

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