98 Dodge 12V engine issue
 

I have a 98 Dodge 12V Cummins with 360K miles on her. Trying to keep her going. Lately (when the air conditioner is on), she dies at a traffic light or if I idle in reverse and hit the brake she dies out. We have no Cummins specific mechanics in our area, so I have to rely on research and fix it on my own....any help or tips are greatly appreciated.