I have a 2001 Ram that is overall a beautiful truck. Recently just did a tuneup and replaced the Cap, Rotor, Pickup Coil, Wires, Plugs and the Ignition Coil. The 5.9 runs strong and is a powerful engine!

I notice that every time I do a hard acceleration, my AC will blow cold air through the defrost vents. After I let off the gas, it returns to the vents that blow directly at you. I’m assuming this could be a bad check valve, as I haven’t seen any cracked lines.

Is there a replacement that works for our 2nd gen rams?

It also would be helpful too though, to know where else to check for potential leaks? I don’t know where all the vacuum lines are located in the truck and would be helpful if there’s any available diagrams on the web!

 

Yes, that sounds like a bad check valve. It should be in one of the vacuum lines coming off the intake. There should be several threads that talk about the wild vent issue on this forum and the types of check valves used to fix the issue. As for the vacuum line routing, I believe that can be found in the service manual. You can download a copy for your year truck via the link below:

https://dodgeforum.com/forum/2nd-gen...e-manuals.html

 

I added to the thread about the wild vents and where to get the check valves. What i have been finding is that they don't hold up for to long and they like to stick(open) in the winter. I want to get a few check valves from this place and see if they perform better than the ones from napa.

 

Boom: