my customer has an early 06 3500 (single wheel) 4x4, ATS stage 4 w/torque converter controller, 5" turbo back with muffler, k&n cold air, and a bully dog tuner (little older one that plugs into the DTC port and modifies on the fly). runs great unloaded and with most trailers. when he hooks to his camper (which is huge) and pulls for usually about an hour it will go into limp mode. most times it will set a P1753 throttle valve actuator mechanical performance. we replaced the actuator but the code persists. the last time he had it out the bully dog pulled a P0102 mass air flow sensor low and a C1340 code in limp mode with no check engine light. by the time he got it to the shop here, without clearing it and limping it all the way here, the C1340 was gone and a C1350 was current along with the P0102 according to the bully dog but when I unplugged it and hooked my verus pro to it I had no current or history codes and but a P1753 and P1740 in pending codes. cleared codes and the truck works as it should again. contacted an rv shop about possibly the trailer being the issue and he advised that it could be the brake controller so we disconnected that and it made no difference. not sure where else to look. maybe the camper itself? maybe pcm? we have left the bully dog disconnected after the p0102 code because given that the truck does not have a mass air flow sensor I thought maybe the tuner was bad. im open to any ideas. thanks in advance.