DC72

just the lightning bolt, not check engine light

Looking for help! This unit runs as a yard truck with PTO for auger/blend system. Normally runs at 1100rpms while pto is engaged. Problem is it will intermittently stumble/hiccup while running on the high idle, sometimes once or twice other times repeatedly. I cannot run this down the road to a dealer to get it plugged in and no one will come here due to age and software needs, internet etc. Any thoughts on what could be causing this? I have already replaced accelerator pedal with solved the problem of occasionally not staying on high idle, originally thought they were the same problem but apparently not! Appreciate any help...Thanks