My 01 Ram with the 5.2L has 77,000 miles on it. It recently had the plenum repair done at the dealer as well as the transmission service and check valve replacement. I called the dealership today and stated that the check valve replacement at the firewall did not solve the problem. When accelerating moderately above 40mph up an overpass with the A/C or Vent on high, the air flow goes from the mid level air vents to the defrost. When I decelerate, it is fine.

The dealership rep stated that there is a second check valve that is probably the culprit and several 2000 and 2001 Rams have the problem. Can someone show me a picture or detail location so I can change the check valve?

Thanks,

jeff

 

Ok...What about a copy of a vacuum diagram for an 01 Ram, 5.2L? Anyone?

 

Jeff,
Try these...

 

I have had the same problem. Now that i know what it is i can fix it.

 

i ahve the same problem, can someone give me an outline on how to fix this problem

 

WayneC:

Thanks for the great photo. I now know I need the manifold check valve.

Jeff

 

Just click on the TSB link above... Step by step instr.

 

I'm at a loss. Both check valves, one at the intake and one at the firewall have been changed and I am still having an issue with air blowing from defrost on steep inclines with it set at vent. I checked below the battery and the vacuum lines are intact. I don't know where to look next. Help please.

 

Check the vacuum lines that run from the intake manifold to the T at the firewall. I broke that one doing a tune up then after connecting the pieces back together we had this problem until I had the whole thing removed and a rubber hose installed the whole length of the plastic vacuum line. I don'tknow why they used plastic lines. I wish they had spent the extra and put rubber lines on there.