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Vacum line on firewall?

625 Views 3 Replies 4 Participants Last post by  Mopar1973Man, 
A
I found a disconnected vacum line going into the firewall right behind the engines valve cover. Anyone know what its for?
I replaced it but notice nothing different.

Thanks.
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BigBlue
It goes to your 4wd actuator on your axle.
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K
it also controls the ducts on your ac. if you disconnect it, it will get stuck in whatever position you left it in. and it also controls your 4x4
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Mopar1973Man
Yeap... The vacuum line controls all your vents inside... But for safety measure it should default to DEF mode... As for the 4WD that is if you have a CAD system.. My 2002 doesn't have this but my Mom's truck does...
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