RE: '89 900; Is there a 'NO HEAT' troubleshooting FAQ?

I just put in a new thermostat but still there is no heat. I bought this car used a few months ago & this is the first time I've tried to use the heater. The old thermostat failed to open when tested in 190 degree (F) hot water. What else could cause the heater to blow cold air other than a clogged heater core?

Reply to
mark
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Hello Mark, The connecting rod between the control knob and the valve may have come off. If the heat knob moves reallllly easily with no resistance that is what is probably wrong. Common problem, easy to fix:

  1. Remove driver side speaker
  2. Locate the the transfer rod, it usually has an orange or white universal joint on the end of it.
  3. Just reach in and slip it back on the heater valve or knob.
  4. Close up the dash.

If you have large hands or an after-market stereo, you may have to remove the stereo from the dash in order to get to the switch side of the transfer rod.

Jeremy

Reply to
Jeremy Brown

That might be it, but...more likely, given that he just had the cooling system open, is that he's got a bubble in the cooling system. There should be a brass bleeder fitting on the firewall near the center, open that up, open up the bleeder on the thermostat housing, and dump water in the fill cap until it starts coming out first the one (close that) and then the other (close that).

Reply to
Dave Hinz

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