Any codes thrown? When mine acts up (whatever it is) I get the P2101 code, and a CEL also. Light goes out after several restarts.I would guess APPS. Mine went out at 135k. Except mine decided to race the engine not dead pedal it like it is suppose to do when it fails. Mine would also not return to idle, keeping the Jake from engaging. Not fun with 12k lbs on a gooseneck.
Aaron