New here and thx for add. Own a 2017 base model 3500hd dually. When demanding throttle it shudders/studders acts erratic. Only kicked code once which was p0191. I cleaned map sensor which was super dirty. 120,000 miles. Just changed fuel filter and motor oil to eliminate that. Not sure if dirty throttle body could be issue or maybe egr? Watched scanner when acting up and seems to maintain 24,000 to 26,000 psi fuel pressure. Any help would be greatly appreciated