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Vacum line on firewall?

625 Views 3 Replies 4 Participants Last post by  Mopar1973Man
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.

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It goes to your 4wd actuator on your axle.
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
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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