1996 Dodge Ram, 3500, Magnum V 10, 4x4, SLT, Dually, 5 speed stick

Hi guys, this is my first thread that I have created (it is not my work but, created from others hard work). I have a Wacky vent situation. I know there is a lot of threads on the subject but, I wanted to compile the information on one thread so I did not have to do the search every time.

DISCLAIMER: Most of this will be copy and paste followed with links. I hope that is okay? I will try to give credit to the major contributors but, there is so many. I can not take credit for any of it.

What I have has been described on quite a few threads but, I am going to add more links than I need, just so it covers most if not all of the issues to do with bad vents, A/C, actuators, vacuum lines etc.

Even if you have corrected your problem and your thread is not being used before or a good thread is not being used, feel free to post it here. May be it will save someone the research time in the future? Add any pertinent information as you see fit if it helps.

This thread is my exact problem:
https://dodgeforum.com/forum/2nd-gen...elerating.html

Note: The last time it was posted on was 08-29-2011, 04:29 PM and no final answer? Hope he did not just sell the vehicle and say forget it?

Also, a combined issue and concern; I recently (3 weeks ago) took my truck into the A/C shop to have it charged (just purchased it). They said the a/c was not at negative pressure. They said it might have a leak in the system. To this point I was about $100 in and no guarantee to charge the system.

They said if I was to charge it and it leaked out, they still would not be able to tell where the leak was unless I had them put die in the line (that was another $100). So, I agreed but, was not happy. They said they would look twice for a leak and it would be at their cost not mine.

Well, 3 weeks later, A/C is pushing less cold air and the above situation. I am going to fix this A/C if I have to do it myself. They said they found no leaks in the system but, would be happy to tear into it. This guy is a rip off, I can tell already. The type of mechanic who has no care for cost to the customer, just pads his own pocket.

If this thread stays open, I will try to post every bit of information I find in my search, with pictures and findings. Hopefully I will be able to find detailed vacuum line drawings or I will scan a hand drawing and upload it to her. Try to give others a clear idea of what I am going through.



I borrowed this picture from jjtroutbum It was posted on another thread (thank you).

Also note: my truck came with cruise control on the steering wheel but, it has no power to it that I can tell. I have a stick shift transmission so, I am still not sure it even came with cruise? 4 wheel drive works great!

Check Valves and Vacuum lines (amazing thread for this):
https://dodgeforum.com/forum/2nd-gen...ild-vents.html
Side Note: From reading this thread, it sounds like I have a bad check valve at the intake.

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

Blend door:
https://dodgeforum.com/forum/2nd-gen...-door-fix.html
https://dodgeforum.com/forum/2nd-gen...d-finally.html
Always fix the obvious stuff first.

The AC on our 06 Durango is not blowing cold:
https://dodgeforum.com/forum/2nd-gen...-ac-wacky.html

Helpful Part Links:

Purolator PCV Valve:
http://shop.advanceautoparts.com/web...ntent=10711125
https://dodgeforum.com/forum/2nd-gen...eck-valve.html

Heater Treater:
http://www.heatertreater.net/?gclid=...FYTJtAodhggA3w

Blower resistor:
https://dodgeforum.com/forum/3rd-gen...a-c-issue.html
http://www.rockauto.com/catalog/more...596&cc=1413414

Final thoughts: bad check valve at the intake, the cruise control servo under the battery, the clean black plastic line is a vac line that runs to the passenger side of the intake manifold and it will crack or break sometimes. also the entire servo will develop cracks every now and then from battery acid dripping on it. so look it over really good. The cad unit bolts onto the front axle. it will have one wire plugged into the left side of it, a black vent hose on top and two vacuum lines plugged into the right side, you can follow the vacuum lines to the transmission mount in the picture above.

You can only blow through the check valves one way. (direction of the arrow.) Install with arrow toward engine. Dealer only item and you only need two. they are cheap. Dodge/Chrysler Part #04549209.

You need to check(trace) the hoses going from the solenoid to the canister for cracks/leaks, and remove it (the canister) and inspect for cracks in the plastic. Also disconnect the hoses from both ends and make sure they are not filled with charcoal. Canister purge solenoid, up on the passenger front fender, where a second battery would go. Canister is under the passenger side rear of the cab.... or, a bit further back.

If it isn't that then it might have something do do with one of the vacuum canisters or lines under that dash that go to the blend door.
You can see a cluster of vacuum lines next to the gas pedal and you can also see the canister that controls the blend door.

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.

The vacuum lines come out of the intake manifold and hit a check valve then a V. The V is there to send the vacuum line down to the cruise control servo and the other side of the V continues onto a T. That T has the line going to the manifold on the inbound side, continues on to the transmission cross member to connect to the CAD unit on the other side and the remaining side goes to another T (toward the passenger fender, away from the intake manifold).

That second T has a check valve on it. One side is connected to the vacuum reservoir (I guess) and the other side (with the check valve) goes into the cab for the vents. Some trucks have a check valve behind the intake manifold on the line that comes off the V and goes down to the cross member.

Special thanks and mad respect to Sheriff420, he made a great thread and kept on top of it, even though it went 20 pages long. There is so many more, if you have one that is useful, please post it here. It's 5:30 am here and I have been working on this since about 8 pm the night before. Thank you all.

 

Okay, guess I am going to need to check my cruise control first. I got under the hood of the truck, felt around, checked the check valve that is attached to the head of the engine, you can blow through it but, can not suck through it (I believe that is good to go). I disconnected the other lines in the area and found I could suck and blow on those and there is no resistance.

I knew going into this that the cruise control did not work but, I figured the truck did not come with cruise because it was a stick shift transmission. Well, I can rest at ease, it did come with cruise, it has the cruise control servo under the battery tray. Fairly certain I will need to pull everything out of there to inspect it for damage.

No matter what the picture says above, there is a lot more to this vacuum system than just a few hoses. lol Mad respect for you guys that have got into this. I will have to start on this when I have more time and less rain. Welcome to Washington weather. It is not green from sunshine.

 

The cruise control servo has been known to basically rot underneath the battery.

 

This is just a couple of diagrams I found. I will verify these are the right ones later as I am investigating.

 

Okay, I figured I would have to pull the battery and the tray to try and get a better look. I may try to figure out some type of drip shield? Not sure what I could do otherwise? The first thing I noticed about the truck was the cruise did not work and then at about 70+ the steering got funky, mild case of "death wobble". It looked good from just what I could see (peeking around the battery but, I really need to be able to get a full inspection going on it. I only want to have to mess with this once, if at all possible.

Thank you for the confirmation on that. I had read the same thing on other threads but, I did not really want to believe it (Cruise Control Servo could be the issue).

 

Here is some pictures I took a few days ago. I have been busy as of late so I have not ripped into the system yet.

 

I'm not sure but it looks like somebody put in a replacement checkvalve. IIRC, the updated checkvalves were huge. lol

 

I know what you mean, I've seen those too. But I think we (v8) owners have one of those too , except it's inside the cowl as opposed to being outside on a v10.

 

I know vacuum lines go through the firewall...so what does that canister thing do!?

 

Vacuum reservoir. According to popular theory, it is supposed to prevent things like wild vents...... I think dodge missed the mark on that one.