99 3500 dually 4x4 with 5 speed, truck was running fine. 3 days ago truck started running funny, "sputters " when you get to about 2500 rpm. runs fine at lower rpms. truck has an edge performance chip and rest of truck is stock. any help would be appreciated. i am posting for him as he is not yet registered and he can check thread later.
thanks
bill

 

Check fuel pressure and check for codes.

Dave