I have a 2001 dodge 1500 5.9 with a bad temper. 7 months ago it started shutting off on me at random points displaying no bus. Immediately following it would start right up. Fast forward to 5 months ago. I was washing my vehicle with an undercarriage wash. When I was leaving the car wash I noticed it was idle at 2500 rpm. In attempts to fix this I replaced the tps maps, iac, cleaned the throttle body and checked to make sure it would close all the way. This didn't fix it. On the way to the shop the no bus shut off came back. This time however it didn't turn back on. After replacing the pcm three times it finally ran again 3 months ago. After finally delivering it to the shop. They replaced the plenum gasket and again replaced the tps, maps, and iac. After they told me it was a bad computer I took it back. No need to keep replacing good parts. While in my garage i managed to find 6 small vacuum leaks. I have pulled every hose and inspected them. I have replaced the pcv valves and seats. I've smoked the system and can find nothing. It idles at 1000-1500 rpm which is causing the shifting to be off at times. If I pump the brakes fast I can get about 500 rpm raise. I am positive this is a vacuum issue but am out of ideas. Please help this nightmare end!

 

Check the lines for the evap system. May have a leak under the truck somewhere.

 

I have already checked all evap lines from gas tank all the way up

 

Maybe start plugging all the main vaccum ports until it idles correctly?

 

This. Disconnect ALL vacuum lines, and plug the ports. See what happens.