Hello all, this evening I was trying to run some wires thru the fire wall and while reaching down in the engine bay this hose right above it snapped(more like the plastic connector eroded away). Not sure what it's for but with the engine running it sucks in air(probably a vac line). But anyone know specifically what it for?

 

If I had to guess, maybe a vacuum line for hvac controls?

 

My guess, too. I think that lower hose might go to the vacuum reservoir in the fender.

 

I know the one on the right of the t, I plugged and havent lost anything... hows the 4x4 working?

 

The one that runs thru the firewall is for HVAC. The unplugged one on the bottom goes to your vaccumn reservoir, and the one on the left goes to your upper intake.

 

Huh... so I'm wondering if I should look into that plugged hose a little more...

 

This

The plastic connector is both a T split and a one-way valve. The hose that goes off to the left is just the vacuum source (goes to the intake on the engine). The hose going off to the right leads into the cabin and is for the HVAC controls. The hose going down that's disconnected goes to a vacuum reservoir in the fender. Don't leave that end open or your have no control over your vents and temps... You're better off capping that one off than leaving it open. You're climate controls will shift (usually to defrost) every time engine vacuum drops (like when getting into the throttle and accelerating up hill), but that's about all that'll happen I believe. That reservoir that the hose goes to is literally just a small plastic air tank that holds vacuum enough to keep everything in the HVAC system working for a while when the engine vacuum fluctuates in just such occasions.

 

It is part of the vacuum system that controls the actuators for the front axle, the transfer-case on 3-button types, and the actuators for the HVAC system. It is likely the connection to the vacuum reservoir that maintains vacuum in the system when the engine vacuum is low when it is under load. The tee-thing is a one-way valve that maintains the vacuum when the engine is under load.

Check out my link in my signature about replacing the hoses on a 4-button transfer case system. It has pictures that I've added that will show much of the routing for the vacuum lines. These are pretty easy to replace (except for some of the ones for the transfer-case if you have a 3-button system) and is well worth doing as it is cheap, easy and you don't have to get under the truck to do it. Well, not get underneath if you have the 4-button system. These hoses will rot and leak a bit to totally fail causing all sorts of problems with your HVAC system and not engage your front axle when you need it most.

 

Thanks all for the replies, I plan on repairing it soon as I get home tonight. I was mostly concerned if I could safely drive it down the street for the day till I get it fixed.

 

Fixed EZ PZ, thanks again all!

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