Hey fellas, been long time since on here, just completed the plenum replacement from hughes about an hour ago, and attacking the vents as well, I came across a line behind the driver side valve cover and has a little disk at the end attatched to a green line, in a binder with the white line can see in the center of the pic, the white line comes from check valve on left side of intake over distributer and down to tranny area, the green is going down as well, but nothing connected to it. 2001 1500 4x4 5.2l

 

That one goes to the either the top of the transfer case or the cad unit. I can check tomorrow.

 

Thanks Sheriff420. could it be a vent to atmosphere line? did find the culprit for crazy vents this morning, was the check valve at the manifold.

but now after the plenum replacement last night, my a/c clutch is getting no power, therefore no a/c. is there a fuse somewhere besides the relay fuse in the wheel well? have unplugged and tested with a dummy light and no juice at the plug, but does have at the relay block.

Edit: found a/c issue and repaird.

 

So I read this thread cause I've been dealing with the wild vents issue since I had the transmission replaced in March and it's been driving me nuts..

I've replaced both check valves (at the T and at the intake manifold), as well as replacing the PCV valve. I did the PCV valve before doing anything else, cause that's a part I could buy immediately (I had to order the check valves). After I replaced the PCV valve, the problem went away for two days (I was soooooooo happy), then it came back.

So I've been sitting here kinda angered that this is still a problem, and I've been noticing some things. When I turn my key to start the truck, it gets to the on position, the blower starts, and the vents are in defrost, even though the selector is on vent, when I start the truck, the air goes to vent after about a second, after I assume enough vacuum has built up to move the door. After I've had the truck running, and the blower is moving air through the vents, if I turn the truck off and then turn the keys right back to the on position, the vents are blowing, but they slowly (over maybe 3 seconds), go to defrost.

So is this indicative that something is wrong behind the dash, since it would seem that the little door thing isn't holding vacuum? I have to be honest, I'm losing my patients with this, and I really can't take the dash down to look at it has Dodge Dash Cancer, aka cracked into pieces, but still holding together.

 

Nope. It's perfectly normal.

This began when the transmission was replaced? If so, someone futzed up. One very common failure to look for is a cracked hard vacuum line in the tangle that runs the CAD. Transmission R&R's quite often kill one of them.

It can be a real pain to hunt down the source of a minor leak like the ones that cause wild vents, but if you dig through the manual and then through the system, proficiently, you'll find it.

Gotta work on that patience if you want to work on vehicles, man.

 

Maybe that new PCV valve is bad. See if they'll let you exchange it. I had to read back a bit to find out that the last time I had the vent issue was due to a bad PCV valve.

 

So I replaced the PCV valve that I just installed from advanced with one I bought from Dodge when I picked up the check valves, with the same results. I had been talking to the dealer about this right after they did the transmission and the mechanic there said that it he did nothing to the vac lines and said that I needed to pay for a diagnostics if I wanted them to find out what the problem is.

I'm mechanically inclined, but only to a certain point. I can do relatively simple things, brakes, rotors, spark plugs. Going into the engine or transmission scare the bejezus out of me cause this is my only vehicle at the moment. I'm not so much angry or inpatient about this as much as I'm dismayed. I was kinda disappointed that the simple cheap problem didn't fix it.

So the CAD.....What is it first I guess, and second, where is it? I'm willing to take a look at least.

 

Does cruise control work? Does the 4x4 engage and disengage normally? And here is info on the CAD(which btw is located on the rear of the right front axle tube).

http://www.dodgeram.org/tech/repair/..._engagment.htm

 

Cruise Control works great, 4x4 works last time I used it, which was late August. I'll get under the truck tomorrow to take a look...

 

Is the check valve in that diagram the same kind of check valve I installed yesterday, and is there any way that this could be caused by a blown plenum, as I know that I have a pretty badly blown one...