Engine serial is PE4045R047339. The PDF document says it has to do with the exhaust throttle valve. I can move it freely. So I am wondering what I should test next ? ! Any one has an idea ? It ran for about 12 hours non stop with very little load when this msg appeared on the DM1 display. I changed the crank filter following a MQ tech suggestion but same problem pops up after 5-10 minutes of running.