i found a loose vacuum line hanging behind my engine when changing my O2 sensors....god only knows how long its been off...and i cant figure out where it came off.......it has a check valve and it comes off a T on the passenger side of the intake.....any ideas ??? could it go to the tranny ? thanks ! my truck is a 2001 1500 4x4 5.2

 

Not to the tranny. It goes into the firewall for the blend and/or mode door in the heater/ac. There should be a stub of it poking through - but as it is small and dark back ther, shine a good flashlight and hopefully you can see it.

 

Does your four wheel drive work? Does your cruise work? Do your vents work? What color was the line??

 

+1 on what color is it? If it's green it does not connect to anything. It's just a vent.