Heater Ac
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Heater Ac
Alright so there might be a ghost in my truck, but I am not sure. The problem is sometimes while running the AC or the heater something happens in the duct control system (I think). You can hear the blower pushing air, but the air stops coming out of the vents like it was, and then 10 minutes or sometimes hours later it starts working again, anyone know what is going on?
97 ford ranger stx ext cab 4.0 4x4 5 speed
97 ford ranger stx ext cab 4.0 4x4 5 speed
Post Fiend
Joined: Jan 2003
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From: Connecticut
Sounds like you might have a small leak in the HVAC system somewhere.
A leak in the vacuum control circuit may occur during acceleration (slow leak), at all times (large leak), or only when specific functions are selected (indicating a leak in that portion of the circuit).
A leak in the vacuum control circuit may occur during acceleration (slow leak), at all times (large leak), or only when specific functions are selected (indicating a leak in that portion of the circuit).
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that is the thing
Thats the thing, it happens at all different times. In san fransisco on a 90 degree day going down the freeway, going through bakersfield in 30 degree weather, driving home in the city from work the other day in 48 degree weather. I can be driving for four hours at the same speed, and it will switch between blowing from the vents, to a loud noise in the dash, at different times. what is the part that controls the louvers between the vents?
Post Fiend
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From: Connecticut
There are small vacuum-controlled valves with levers attached to doors in the HVAC system. Engine manifold vacuum is used to actuate the valves so as to open and shut the doors in a certain manner (and to a certain degree) in order to route the air to a specific vent locaton. The main vacuum control assembly is attached to the back of the climate control switch that's on the dash.
Post Fiend
Joined: Jan 2003
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From: Connecticut
Right. The control assembly (the **** that chooses Defrost, Vent, Floor, etc.) has vacuum lines going into the back of it.
To access the back of the HVAC control assembly, remove the radio and then pull the finish panel back and then up.
The red vacuum hose at the control assembly goes to the Panel/Defrost door vacuum motor. The yellow and blue hoses go to the Panel/Floor door vacuum motor. The white hose goes to the hot water valve (in engine compartment) and the outside/recirculation air door motor. The black hose is the main vacuum feed from the engine manifold (vis a vis a vacuum storage tank and check valve).
To access the back of the HVAC control assembly, remove the radio and then pull the finish panel back and then up.
The red vacuum hose at the control assembly goes to the Panel/Defrost door vacuum motor. The yellow and blue hoses go to the Panel/Floor door vacuum motor. The white hose goes to the hot water valve (in engine compartment) and the outside/recirculation air door motor. The black hose is the main vacuum feed from the engine manifold (vis a vis a vacuum storage tank and check valve).
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