Another air condition ?

[aka rotten]

A few posts down gentelman was askin about air suddenly blowing on winshiels instead of out the vents while pressing gas pedel.I have this same problem in my 2000 Expy.Now i understand its vacum lines,can someone give me idea where to look for these on a 4.6 engine?I,m in wheelchair and my son will help but i,d like to know where to start lookin for them.Thanks Gents

 

[2000eb]

There is a little valve on the passenger side corner of firewall three lines are going to it and alot of times thats ur problem