Cm 2350 surging at high idle

[gearhead]

These are very sensitive to charge flow and egr flow leaks any leaks will cause serging at no load. listen to turbo you will hear it. Also fuel pressure being low can cause this ecm trying to overcome low pressure so pressure moving around could be problem. Without laptop you can check for leaks before and after egr and also boost leaks. But much better to have laptop.