Engine spits and sputters when under a load. Won't miss any at all if you rev it wide open and don't move. Turn on PTO and put it under a small load and it starts sputtering. Checked fuel filter and it's fine
My co-worker has the same problem with his Kohler EFI, and it turned out to be a faulty ECU module. Dealer told him it is the third one he's had to replace.
Make sure that any wiring harness grounding connections to the frame of your mower are tight and secure and no rust. I've seen the EFI's do the same thing with a faulty ground to the ECU. Especially on a frame that was powder coated from the factory.
