Hello, I'm not a pro, but I need help from you guys. I was mowing with my Lazer Z (72" EFI) this afternoon cutting mainly dry grass from last year. I ran into some think green weed with the deck fairly low which bogged it down some. I did what I usually do, stop and let the mulching kit chop it up and get back up to speed before moving on. However, this time the blade speed did hold its normal full throttle speed consistently. It seems to have an eratic speed at full throttle speeding up and slowing down a little over and over. I tried raising the deck and getting into a clear area with no difference. I shut off the PTO clutch and the engine seems to run just fine at full throttle. I looked under the deck and did not see anything unusual or any buildup. Any suggestions? Thanks for any help.