Thank you Guys,

Do you really know what that vacuum switching valve is for .......like what circuit is it?

I know what it is and how it works ....It opens and closes to turn on and off the vacuum for something... Its the something that I was also trying to figure out. I know I found it broke after i had the whole intake manifold and air plenum apart for thermostat replacement. I was troubleshooting the cause for such ***** gas mileage on my drive back from Utah right after teh maintenance.

Any one know what it it is for ?

Glassen 1999 Rodeo LS
"Wishing I had the money for a Calmini lift kit"