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What is your question?
Happens intermittently. Suddenly no air flow from any vents. No heat or AC.
2 Replies
possible failing blower motor,it's going on 20 years old.you could check the connector,and/or pull the blower motor out and run it,see what happens,BEFORE it starts getting cold in WA!if you end up needing a new motor,then here is one without the wheel,use your old wheel,also you would need to splice the wires with a crimping tool or solder the wires.they also have one just plug and play with the wheel also on it. for around 12 bucks more.check all connections,fuses,relays,maybe loose,before REPLACING anything. VDO/A/C Heater Blower Motor Part Number: PM3922 Warranty: Limited Lifetime Notes: Wheel not included Fits front and/or rear Price: $56.99 Everco/A/C Heater Blower Motor Part Number: 75788 Warranty: Limited Lifetime Notes: Wheel included Front unit Price: $68.99
It's not cutting the air flow completely off ... It IS switching to the defrost mode because of a vacuum leak from engine to the HVAC control..!! The air mode selector is VACUUM controlled ... Just for kicks, check the defrost for air flow next time this happens... (Those are small 'capillary' vacuum tubings hooked to the rear of air flow selector switch... They're not wires) .. System can be easily tested!
No, sorry, thanks for your help. It is not going into defrost mode. We first noticed the problem when we had a van full of people and the defrosters quit. It was very difficult for my wife to keep the windows clear enough to get home. All the people breathing were making a mess of the window. Air flow does not completely stop but very very low. The temperature control door valve/actuator is electric. All the rest are vacuum. Can a failure of the temperature door control valve cause almost complete loss of air flow out of all vents?? The shop manual seems to indicate that is the problem. BTW, IT IS A 1997 EXPRESS VAN 1500. Also thinking I could tee a vacuum gauge into main supply and see if it drops when HVAC fails? Thanks again for helping. I believe a good shop tested the vacuum with gauges. This is a tuff one and intermittent! They put way more hours into it than the billed us. Frustrating as I drove it all over Seattle to make it fail for their main guy. He recommended a new control panel complete with knobs etc. Didn't change a thing!
No problem. I'll find it and fix it - too stupid to quit and too broke to pay someone else. Have a great day! Duf
When all else fails.... Diagnostic flow chart (optional) ... + > A Mighty-Vac tester make this SOooo simple!!
Thanks guys. I think it could be the blend door actuator losing vacuum. And I'll get one of those mighty-vac testors. Have a good 1!!
Thanks much. Nope not the blower. It doesn't change speeds just keeps blowing away but a door that cuts off air flow has shut somewhere so it gets a muffled sound. I suspect a couple of things. There is an electric heater air temperature valve that controls a door that directs air either thru the heater core or not -this is run by the temperature control knob on the dash. Also there is a set of "mode doors" that control the flow of air either to instrument panel or down low - maybe they are shutting. Dang thing is, it is intermittent so I am going to try to mark these door positions when it is working and then drive it until it fails and then check the door positions.... PITA!