Hello everyone I'm new to this site and need some help.
I have a 1998 dodge ram 1500 4x4 5.2L My a/c or heater only blows out the defrost vents no matter what setting or idle or high rpm. My truck died on me once waiting to turn left. I was on the brakes so I was wondering if it's a vacuum leak that is causing it to die or stall? Is this the wild vent problem I've read about or something else a/c wise? Other then that it runs good i used it all year

 

Vacuum leak. Need to find it.

 

Your symptoms describe a vac leak. On mine I discovered that one of the black plastic lines was broken, but not completely, visually it looked fine, it wasn't until I moved the line did the break become apparent.

 

Mine had a leak in the cruise control servo. The one way check valve was also bad, it was more of a restriction allowing vacuum both ways. There's a vacuum reservoir in the cowl to check also.

 

Well I checked it today and noticed one of the plastic lines. I took a pic and wondering where it goes and where to buy that line or can a rubber hose be used instead so it won't crack again?

 

That would explain it. Of course, that line goes thru the firewall there, right by the a/c line.... and I don't see the other side of it.

 

If you are lucky you may be able to see a tiny bit still sticking out into the engine bay, some painful contortions and a pair of hemostats may be able to pull 1/4 inch out, which is just enough to stick a small piece of vac hose on it to act as a coupler. If not you will be spending a lot of time trying to find that line up behind the dash, which , from what I've seen is next to impossible. I don't have enough experience with these to suggest a work around. However, I had a similar problem on another dodge, and I was able to finally figure out what line under the dash I could hook a vac hose to, and by carefully drilling a small hole in the firewall, ran another vac feed line for the blend , all hope is not lost. Unfortunately I don't have access to a computer at home, so I have no service manual to point you in the right direction. Never fear, someone will be along shortly. That's the exact hose on mine that broke, but a lot farther from the firewall.

 

Well I did not see the other piece sticking out the firewall so I guess it's on in there. Do y'all think I should try an pull that line out the firewall and piece it or should I just find a new line to put in it? I would hate to try and piece it and later it just break somewhere else cause it's so old. But I'm not trying to rip the dash apart or spend alot of time fixing it. I'm sure I'll have to anyways. What is that right where it broke a check valve? Should that be replaced also?

 

Yes that's a check valve. You should only be able to suck through it one way.

 

Well today I was looking over the vac lines and the others seem to be fine. Cannot find the 1 broke in the firewall so I guess I have to tear the dash apart? Any tips or tricks to get to that vac line beside the a/c line? Do I need to pull the whole dash or can I take the glove box out an get to it? I've never pulled a dash on a dodge so if y'all know the easiest and quickest way to do it, I'm all ears an would appreciate any ideas to point me the right way to do it