Annoying hiss coming from climate control

[RobertPhilbeck]

Hello all,
My first post to this board. I just bought my Explorer this past August, and its had an annoying hissing, sucking vacume sound coming from the climate controls.
It only appears when the control is set to the, "off" position. Its the loudest when im moving slow, or standing still. It fades out as I accelerate.
Does anyone else have this problem, or know how to fix it? Id like to save myself a trip to the dealer if its an easy fix.

Thanks,
Robert

 

[Bartman]

Robert,

Welcome to the site! You'll find info on everything about Explorers here. If you are like me, you'll soon get hooked on reading the posts, even if you have no questions. You'll learn a lot about what you can do with your Explorer. But beware of the mod bug!! Now, on to your problem.

I also have a 2000 XLT. So far, I have not had the problem you described. Is there any engine performance problems that you've noticed (low MPG, etc)? I was thinking maybe a loose air or vacuum hose in the engine. Maybe you wouldn't notice the hissing sound under acceleration or when the fan is running.

Sorry I couldn't help more.

John

 

[Bartman]

Robert,

I forgot to ask which engine you have. It might not be important, but then again, maybe it is. You might want to post that info. in case other people have more suggestions on this than I do.

 

[JDraper]

Hi Robert,
A good probability is a vacuum leak in the unit. My wife's Firebird did that, and one of the vacuum tubes had gotten brittle and cracked. To get to the unit (at least on my 2001) there are two screws in the overhang above the heater controls. Once those are out, the whole radio/ac/heater module and housing should slide out and you can access the back of the unit. Hope that helps

 

[Ray Hutchinson]

Hiss

Had a similar problem on my '93. Turned out to be an unplugged 1/8"(i.d.) vacuum line located inside the Engine Compartment, on the firewall, adjacent to the Heater/AC unit.. It controlled the fresh air vent "flapper" and this wouldn't close all the way with the line unhooked, so I had a slow flow of cool outside air, and could hear the hiss from the vacuum leak. Surprisingly, even with the leak, I didn't seem to experience any performance problems. The Fix: just reconnect the vacuum line.