Bingo! I finished my Echo PE 2000 today (my last "Planned" winter project) and it worked after exploring 3 yrs. The monster would start easy and idle good BUT! No Wide Open Throttle. I was stripping it as a parts machine when I noticed the fuel filter looked intentionally blocked with what appeared as a solid disc assembled between the dead weight and element material. With the disc removed the filter w/n allow the trimmer or my working chainsaw to run at WOT.

I thought I had finally traced the problem before donating the engine. Nope! But I spotted the limits on the mixture screws and promised that would be my last effort (by cutting the limits to allow full revolutions adjusting the mixtures). It ran like a Dream with approx 2 turns out each screw. loger