Vaccum Leak?

[Mobile22]

Does anyone know if there are vacum lines running into the dash behind the cluster? With the A/C off I swear I hear a slight vaccum leak coming from the dash. I can't tell if it goes away under throttle because the truck is too loud. Stock boost gauge works and I don't think it's coming from there.

If there is...where and what does it run too and whats the best way to get to it?

 

[bundie]

Re: Vaccum Leak?

HVAC control is vacuum operated.

 

[bigmileage]

Re: Vaccum Leak?

Yup, HVAC is vacuum operated. If you have a vacuum leak you won't get vent operation, the system will default to defrost/floor operation (dependent upon leak size).

 

[randy merritt]

Re: Vaccum Leak?

On my sy, I have to move the right hand selector lever just slightly up when in the "off" position. If I don't do this, there is a vaccum leak that you can hear behing the dash control area.

 

[atkonkler]

Re: Vaccum Leak?

I also to have a vaccum leak in my dash I just wish I could find someone to drive mine while I hang upside down to better idea of where it's coming from!

 

[bigmileage]

Re: Vaccum Leak?

Just get it smoked, most reputable shops have a nitrogen machine to smoke the system with. Very easy and fast. I've had to smoke the vacuum system on my Regal several times to find small vacuum leaks, without a machine like that it's almost impossible.