Is it normal to have vent registers switch to floor under boost?

[tnsyty]

Mine has always done this. Driving with vents on, and as soon as you get into boost it goes to floor registers. Do I have a check valve in the wrong place, or do they all do it?

 

[93ty475]

Re: Is it normal to have vent registers switch to floor under boost?

sounds like you need a one-way check valve installed between the vac source and the hvac...also make sure your vacuum tank is functioning and/or plumbed correctly...

 

[tnsyty]

Re: Is it normal to have vent registers switch to floor under boost?

Sounds like more stuff to do at the Nationals. I need a good diragram for vacum hoses. I have a check vavle messed up somewhere under the hood aparently. It also messes with my cruise control.

 

[JKsSyclone]

Re: Is it normal to have vent registers switch to floor under boost?

Your truck always has strange things wrong with it. :lol:
You need to just rip out all of the old vac. lines and start all over. I bet it would fix the boost leak too. :tup:

 

[tnsyty]

Re: Is it normal to have vent registers switch to floor under boost?

I need a vacuum line kit for it. I don't have a boost leak, I have an abundance of boost. From what I have read on here, i need an external WG because of my cat delete. I think I know someone who has a spare lying around too, lol.