0299 code today

[billy2006]

was pulling 7500lbs trailer today when going up a hill truck downshifted and boost gauge went up to 29 psi never been over 25 and my edge box started flashing acode that said low boost but truck seems fine cleared the code and drove about 45 miles and stopped for lunch, started truck again and same code again what would cause this. cheched all fluids seem fine no puking of radiator resoivor cap , still has boost will run it up tommorow without load

[late_99_PSD]

Bad MAP sensor

[dazdillenger]

I'd say map sensor, or the t plug where the edge plugs in to the map sensor si loose.