2004 XLT Vacuum leak

[harleyrider90]

I have a question.. My vent switches to defrost under acceleration.. I've read where to look for leaks and I replaced a few bad spots in the system.. I sprayed starting fluid all over the lines and there's no more leaks.. But the problem is still there? I've looked under the dash and the controls everything looks good... Where should I look next? Thanks in Advanced!..

 

[harleyrider90]

Ok I just tested everything with a hand pump.. I don't have any leaks... Everyplace I tested held vacuum for 2 min test on each line under the hood and behind the switch inside... I replaced the pcv valve fix multiple cracks in the lines tried starting fluid to test for leaks... I'm out of ideas... Would Like any ones input... Thanks

 

[GAINMOB]

no clue