Hello,
I have a '96 B2500 with 5.9. About 2 years ago we had a new/rebuilt (jasper) engine put in it because it had a rod knocking. Not too long after that we noticed the idle was a little rough. Over the year or two it has gotten to the point of being real rough. Idles smooth while cold, as it warms it gets to a point where it increases 300 RPMs or more then drops off.
The manual says check vacuum first. I did this today and found a busted line from the throttle body to some kind of solenoid. I replaced that line, the PCV, and air filter, the condition is still there.
After some research and study I think the MAP or Intake Air sensors could cause my problem. Before outlaying that kind of money to see if a replacement would work, is there anything else I should be concerned with?
Thank you, Fred