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hiss from temperature controls at idle

all these little problems...my old one might have done the same thing, but i assume since i just bought this i'm super-sensitive to every little thing

if the vent/ac knob is on OFF at idle, there is a slight hiss. if you put it on any other setting you can hear the fan/air as expected. also, its hard to tell but it seems like once you rev it a little or get moving it quits.

any ideas?
 

blacksnapon

Moderator
Staff member
9,461
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waynesville,mo.
Look on the rear of the control. Because it is vacuum controlled (the mode/temperature selectors) you probably have a vacuum leak. At idle, the vacuum is stronger. When you are at speed, or accellerating, vacuum drops. Thats why you dont hear it as much.
 

blacksnapon

Moderator
Staff member
9,461
301
waynesville,mo.
When you remove it from the dash, there is a small plug with 5 (I think) vacuum lines in it. Its easy to see when the control is loose. Only one is the supply from the engine. The plug is usually held on by one or two nuts or screws.
 
cool - i'll check tonight and let you guys know
(obviously not super-pressing, so it could be a couple days)
 

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