Alas, it may be. Try dropping the glovebox door and looking at the actualor on the top of the heater plenum. You should see it rotate in response to changes in the temperature control. If it is moving and you've already checked the heater hoses, then it is probably the broken shaft on the blend door. If it isn't moving, check the motor leads for voltage to determine if the motor is shot or you aren't getting a drive command. All of these latter options are easier fixes than the blend door, I'm afraid.
=Vic= Bear Gap, PA
"todd harms" said:
Have a 99 X Sport with 53k on the clock and found out this morning there is
> no heat. Temp gauge moves up and stays where its supposed to, heater core
> lines are warm, (one warmer than the other), Rad fluid is up where its
> supposed to be in overflow and in radiator so i am wondering if this is the
> dreaded blend door problem? or is it possible i could have dirt covering
> fins on heater core? If someone could confirm or deny my suspicions i would
> appreciate it.
>
> toddles
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