Bought a used Echo PE266 from an online aucton. It starts great and runs up to mid speed then seems to max out. It's obvious this machine hasn't had a lot of usage. Since I have a new 266 trimmer that runs great, I've tried swapping a lot of parts with no success. Here's what I've done: Checked exhaust port--clear Checked compresson--140 Changed fuel line and filter Adjusted high speed jet Installed new sparkplug--NKG BPM8Y Swapped carbs with new 266 (carb on problem unit runs great on new 266) Swapped mufflers Swapped carb mounting block (not sure exactly what it's called) Swapped coils Tried running without drive shaft--just in case it was a problem with gearbox Fuel is fresh 93 octane/no ethanol, Amsoil (runs great in new 266 and other equip) What am I missing? Is it possible that the intake porting is blocked--exhaust port was clean so I doubt the engine has major carbon. Would love to get this running. My new 266 has been great so far--only a couple weeks usage on it.