I am having issues with my 2004 LLY surging when I am going down the road. I had fault code P0652 and I replaced the APP and also tested the other sensors that are on the same circuit. All the sensors tested ok but my trucks still surges anywhere from 50-300 rpms. I changed my fuel filter twice in that past month and I am running out of ideas. Did anyone else have this issue with your truck?

Are you running any fuel additives? Do you have any modifications to your truck? Please take a moment and fill out your signature (Click User CP then Edit Signature). That will help us understand your situation better and offer more educated opinions.

I'd try adding a quart of Power Service Diesel Kleen to your tank to ensure your injectors are clean. Besides that, you'll need to tell us more about your truck.

Good luck!